text
stringlengths
49
983k
#include <bits/stdc++.h> #pragma comment(linker, "/STACK:60000000") using namespace std; const long double eps = 1e-9; const int inf = (1 << 30) - 1; const long long inf64 = ((long long)1 << 62) - 1; const long double pi = 3.1415926535897932384626433832795; template <class T> T sqr(T x) { return x * x; } int n, m, k; char a[50][50]; const int dx[4] = {1, -1, 0, 0}; const int dy[4] = {0, 0, 1, -1}; bool u[256]; int d[50][50]; pair<int, int> q[2500]; string bfs() { memset(d, 255, sizeof(d)); pair<int, int> S, T; for (int i = 0; i < (int)(n); i++) for (int j = 0; j < (int)(m); j++) { if (a[i][j] == 'S') S = make_pair(i, j); if (a[i][j] == 'T') T = make_pair(i, j); } d[T.first][T.second] = 0; int h, t; h = t = 0; q[h] = T; while (h <= t) { pair<int, int> v = q[h]; h++; for (int i = 0; i < (int)(4); i++) { pair<int, int> w = make_pair(v.first + dx[i], v.second + dy[i]); if (0 <= w.first && w.first < n && 0 <= w.second && w.second < m && d[w.first][w.second] == -1 && u[a[w.first][w.second]]) { d[w.first][w.second] = d[v.first][v.second] + 1; t++; q[t] = w; } } } if (d[S.first][S.second] == -1) return "S"; string res = ""; vector<pair<int, int> > V, W; V.push_back(S); int cd = d[S.first][S.second]; while (cd > 1) { char c = 'z'; for (int i = 0; i < (int)(V.size()); i++) for (int j = 0; j < (int)(4); j++) { pair<int, int> w = make_pair(V[i].first + dx[j], V[i].second + dy[j]); if (0 <= w.first && w.first < n && 0 <= w.second && w.second < m && cd - 1 == d[w.first][w.second]) c = min(c, a[w.first][w.second]); } res += c; W.clear(); for (int i = 0; i < (int)(V.size()); i++) for (int j = 0; j < (int)(4); j++) { pair<int, int> w = make_pair(V[i].first + dx[j], V[i].second + dy[j]); if (0 <= w.first && w.first < n && 0 <= w.second && w.second < m && cd - 1 == d[w.first][w.second] && a[w.first][w.second] == c) W.push_back(w); } sort(W.begin(), W.end()); W.resize(unique(W.begin(), W.end()) - W.begin()); cd--; V = W; W.clear(); } return res; } string res; void calc(int cur, int la) { if (cur == 26) { string tmp = bfs(); if (tmp == "S") return; if (res == "S") res = tmp; else if (res.length() > tmp.length() || (res.length() == tmp.length() && res > tmp)) res = tmp; return; } calc(cur + 1, la); if (la == 0) return; u[cur + 'a'] = 1; calc(cur + 1, la - 1); u[cur + 'a'] = 0; } int main() { cin >> n >> m >> k; for (int i = 0; i < (int)(n); i++) for (int j = 0; j < (int)(m); j++) cin >> a[i][j]; memset(u, 0, sizeof(u)); u['S'] = 1; u['T'] = 1; res = "S"; calc(0, k); if (res == "S") cout << -1 << endl; else cout << res << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int bcount[1 << 12]; set<pair<int, int> > done; string Map[60]; int n, m, k; int dx[] = {-1, 1, 0, 0}; int dy[] = {0, 0, -1, 1}; int ex, ey; int absval(int x) { return x < 0 ? -x : x; } int dist(int ax, int ay, int bx, int by) { return absval(ax - bx) + absval(ay - by); } struct pqitem { int x, y; string S; int mask; bool operator<(const pqitem &b) const { if (S.size() + dist(x, y, ex, ey) == b.S.size() + dist(b.x, b.y, ex, ey) && S.compare(b.S) > 0) return S.compare(b.S) > 0; else return S.size() + dist(x, y, ex, ey) > b.S.size() + dist(b.x, b.y, ex, ey); } }; int getbcount(int m) { int ret = 0; while (m > 0) { ret += bcount[m & ((1 << 10) - 1)]; m >>= 10; } return ret; } int main() { for (int i = 1; i <= (1 << 10); i++) bcount[i] = bcount[i / 2] + (i & 1 ? 1 : 0); cin >> n >> m >> k; for (int i = 0; i < n; i++) cin >> Map[i]; int x, y; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { if (Map[i][j] == 'S') x = i, y = j; if (Map[i][j] == 'T') ex = i, ey = j; } priority_queue<pqitem> q; q.push((pqitem){x, y, "", 0}); bool found = false; while (!q.empty()) { pqitem cur = q.top(); q.pop(); if (cur.x == ex && cur.y == ey) { cout << cur.S << endl; found = true; break; } if (done.find(make_pair(cur.x * m + cur.y, cur.mask)) != done.end()) continue; done.insert(make_pair(cur.x * m + cur.y, cur.mask)); for (int d = 0; d < 4; d++) { pqitem nxt = cur; nxt.x += dx[d]; nxt.y += dy[d]; if (!(nxt.x >= 0 && nxt.x <= n - 1 && nxt.y >= 0 && nxt.y <= m - 1)) continue; if (Map[nxt.x][nxt.y] != 'T') { nxt.mask |= (1 << (Map[nxt.x][nxt.y] - 'a')); nxt.S += Map[nxt.x][nxt.y]; } if (getbcount(nxt.mask) <= k) q.push(nxt); } } if (!found) printf("-1\n"); }
#include <bits/stdc++.h> using namespace std; const int N = 55; int R, C, KK; char ssG[N][N]; int stx, sty; struct nodexx { string str; int x, y, val; nodexx(string str00, int x00, int y00, int val00) { str = str00, x = x00, y = y00, val = val00; } bool operator<(const nodexx t) const { int lenaa = str.size(), lenbb = t.str.size(); if (lenaa - lenbb) return lenaa > lenbb; return str > t.str; } }; priority_queue<nodexx> QQ; set<pair<pair<int, int>, int> > SET; int has[N][N]; int dirc[4][2] = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}}; bool Judge(int x) { int cnt = 0; while (x > 0) { cnt += x % 2; x >>= 1; } return cnt <= KK; } string BFS() { SET.clear(); memset(has, 0, sizeof has); while (QQ.size()) QQ.pop(); QQ.push(nodexx("", stx, sty, 0)); SET.insert(make_pair(make_pair(stx, sty), 0)); int e, r, c, t; while (QQ.size()) { nodexx XA = QQ.top(); QQ.pop(); for (e = 0; e < 4; e++) { r = XA.x + dirc[e][0], c = XA.y + dirc[e][1]; if (r >= 0 && r < R && c >= 0 && c < C && ssG[r][c] != 'S') { if (ssG[r][c] == 'T') return XA.str; t = XA.val | (1 << (ssG[r][c] - 'a')); if (Judge(t) && SET.count(make_pair(make_pair(r, c), t)) == 0) { if (has[r][c] && (has[r][c] & t) == has[r][c]) continue; has[r][c] = t; SET.insert(make_pair(make_pair(r, c), t)); QQ.push(nodexx(XA.str + ssG[r][c], r, c, t)); } } } } return "-1"; } void cyh() { cout << BFS() << endl; } int main() { int e, f; while (cin >> R >> C >> KK) { for (e = 0; e < R; e++) { scanf("%s", ssG[e]); for (f = 0; f < C; f++) if (ssG[e][f] == 'S') stx = e, sty = f; } cyh(); } return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = 1000000000; const int dy[4] = {0, 0, -1, 1}; const int dx[4] = {1, -1, 0, 0}; int n, m, k; vector<string> s; pair<int, string> answ; bool us[26]; void get_way() { int d[50][50]; bool used[50][50]; pair<int, int> from[50][50]; int sy, sx, ty, tx; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { d[i][j] = 1000000000; if (s[i][j] == 'S') { sy = i; sx = j; } if (s[i][j] == 'T') { ty = i; tx = j; } used[i][j] = false; } d[ty][tx] = 0; queue<pair<int, int> > q; q.push(make_pair(ty, tx)); while (!q.empty()) { int cury = q.front().first; int curx = q.front().second; q.pop(); for (int i = 0; i < 4; i++) { int toy = cury + dy[i]; int tox = curx + dx[i]; if (toy >= 0 && toy < n && tox >= 0 && tox < m && d[toy][tox] == INF) { if (s[toy][tox] != 'S' && s[toy][tox] != 'T' && !us[s[toy][tox] - 'a']) continue; d[toy][tox] = d[cury][curx] + 1; q.push(make_pair(toy, tox)); } } } if (d[sy][sx] == INF) return; vector<pair<int, int> > st, st2; st.push_back(make_pair(sy, sx)); used[sy][sx] = true; while (true) { for (int i = 0; i < st.size(); i++) { int cury = st[i].first; int curx = st[i].second; for (int j = 0; j < 4; j++) { int toy = cury + dy[j]; int tox = curx + dx[j]; if (toy >= 0 && toy < n && tox >= 0 && tox < m && d[cury][curx] - d[toy][tox] == 1 && !used[toy][tox]) { used[toy][tox] = true; from[toy][tox] = make_pair(cury, curx); if (st2.size() == 0) { st2.push_back(make_pair(toy, tox)); } else { if (s[toy][tox] < s[st2[0].first][st2[0].second]) { st2.clear(); st2.push_back(make_pair(toy, tox)); } else if (s[toy][tox] == s[st2[0].first][st2[0].second]) { st2.push_back(make_pair(toy, tox)); } } } } } st = st2; st2.clear(); if (st.size() == 0) break; } string ans = ""; int cy = ty, cx = tx; while (true) { int tty = from[cy][cx].first; int ttx = from[cy][cx].second; if (tty == sy && ttx == sx) break; ans += s[tty][ttx]; cy = tty; cx = ttx; } reverse(ans.begin(), ans.end()); if (d[sy][sx] < answ.first) { answ = make_pair(d[sy][sx], ans); } else if (d[sy][sx] == answ.first && ans < answ.second) { answ = make_pair(d[sy][sx], ans); } } void rec(int cur, int cnt) { if (cnt == k) { get_way(); return; } for (int i = cur; i < 26; i++) { us[i] = true; rec(i + 1, cnt + 1); us[i] = false; } } int main() { cin >> n >> m >> k; for (int i = 0; i < n; i++) { string str; cin >> str; s.push_back(str); } answ = make_pair(INF, ""); rec(0, 0); if (answ.first == INF) { cout << -1; } else cout << answ.second; return 0; }
#include <bits/stdc++.h> #pragma comment(linker, "/STACK:256000000") using namespace std; const int maxN = 52; int n, m, k; char s[maxN][maxN]; int d[maxN][maxN]; char f[maxN][maxN]; int px[maxN][maxN], py[maxN][maxN]; bool allowed[maxN]; string res; int length = 1000000; int sx, sy; int fx, fy; bool isOk(int x, int y) { return 0 <= x && x < n && 0 <= y && y < m && (s[x][y] == 'S' || s[x][y] == 'T' || allowed[s[x][y] - 'a']); } int dx[] = {-1, 0, 0, 1}; int dy[] = {0, -1, 1, 0}; void check() { queue<pair<int, int> > q; for (int i = 0; i < n; ++i) { for (int j = 0; j < m; ++j) { d[i][j] = 1000000000; f[i][j] = 'z'; } } q.push(make_pair(fx, fy)); d[fx][fy] = 0; while (!q.empty()) { pair<int, int> current = q.front(); q.pop(); int x = current.first; int y = current.second; for (int i = 0; i < 4; ++i) { int nx = x + dx[i]; int ny = y + dy[i]; if (isOk(nx, ny) && d[nx][ny] > d[x][y] + 1) { d[nx][ny] = d[x][y] + 1; f[nx][ny] = s[x][y]; px[nx][ny] = x; py[nx][ny] = y; q.push(make_pair(nx, ny)); } else if (isOk(nx, ny) && d[nx][ny] == d[x][y] + 1) { if (s[x][y] < f[nx][ny]) { f[nx][ny] = s[x][y]; px[nx][ny] = x; py[nx][ny] = y; } } } } if (d[sx][sy] - 1 > length) { return; } string current = ""; int x = sx; int y = sy; vector<pair<int, int> > candidates; candidates.push_back(make_pair(x, y)); int len = d[x][y]; while (len > 1) { vector<pair<int, int> > ncandidates; char value = 'z'; for (int i = 0; i < candidates.size(); ++i) { int cx = candidates[i].first; int cy = candidates[i].second; for (int j = 0; j < 4; ++j) { int nx = cx + dx[j]; int ny = cy + dy[j]; if (isOk(nx, ny) && d[nx][ny] + 1 == d[cx][cy]) { if (s[nx][ny] < value) { ncandidates.clear(); ncandidates.push_back(make_pair(nx, ny)); value = s[nx][ny]; } else if (s[nx][ny] == value) { ncandidates.push_back(make_pair(nx, ny)); } } } } current += value; sort(ncandidates.begin(), ncandidates.end()); candidates = ncandidates; candidates.resize(unique(candidates.begin(), candidates.end()) - candidates.begin()); --len; } if (current.size() < length || (current.size() == length && current < res)) { length = current.size(); res = current; } } void rec(int index, int cnt) { if (cnt <= k) { check(); } if (cnt == k) { return; } for (int i = index; i < 26; ++i) { allowed[i] = true; rec(i + 1, cnt + 1); allowed[i] = false; } } int main() { cin >> n >> m >> k; for (int i = 0; i < n; ++i) { cin >> s[i]; } for (int i = 0; i < n; ++i) { for (int j = 0; j < m; ++j) { if (s[i][j] == 'S') { sx = i; sy = j; } if (s[i][j] == 'T') { fx = i; fy = j; } } } rec(0, 0); if (length == 1000000) { cout << -1 << endl; return 0; } cout << res << endl; return 0; }
#include <bits/stdc++.h> using namespace std; template <class T1, class T2> ostream& operator<<(ostream& os, const pair<T1, T2>& p) { os << "{" << p.first << ", " << p.second << "}"; return os; } template <class T> ostream& operator<<(ostream& os, const vector<T>& p) { os << "["; int i = 0; for (typename vector<T>::const_iterator it = p.begin(); it != p.end(); ++it) { os << (i == 0 ? "" : ", ") << *it; i++; } os << "]"; return os; } template <class T> ostream& operator<<(ostream& os, const set<T>& p) { os << "["; int i = 0; for (typename set<T>::const_iterator it = p.begin(); it != p.end(); ++it) { os << (i == 0 ? "" : ", ") << *it; i++; } os << "]"; return os; } template <class K, class V> ostream& operator<<(ostream& os, const map<K, V>& p) { os << "["; int i = 0; for (typename map<K, V>::const_iterator it = p.begin(); it != p.end(); ++it) { os << (i == 0 ? "" : ", ") << *it; i++; } os << "]"; return os; } template <class T> string toString(const T& o) { stringstream ss; ss << o; string ret; getline(ss, ret); return ret; } template <class T> vector<T> subv(const vector<T>& v, int from, int to) { return vector<T>(v.begin() + min(max(0, from), (int)v.size()), v.begin() + min(max(0, to), (int)v.size())); } pair<int, int> operator+(const pair<int, int>& a, const pair<int, int>& b) { return make_pair(a.first + b.first, a.second + b.second); } pair<int, int> operator*(const int& a, const pair<int, int>& b) { return make_pair(a * b.first, a * b.second); } vector<vector<int> > a; int si, sj, ti, tj; int f[64][64]; int n, m; int d[4][2] = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}}; int c1, c2, c3, c4; void go() { queue<pair<int, int> > q; queue<int> st; q.push(make_pair(si, sj)); st.push(1); while (q.size()) { pair<int, int> p = q.front(); q.pop(); int step = st.front(); st.pop(); if (f[p.first][p.second] != 0) continue; f[p.first][p.second] = step; step++; for (int k = 0; k < 4; ++k) { int x = p.first + d[k][0]; int y = p.second + d[k][1]; if (0 <= x && x < n && 0 <= y && y < m) { int& v = a[x][y]; bool ok = (v == c1 || v == c2 || v == c3 || v == c4); if (v < 0 || ok) if (f[x][y] == 0) { q.push(make_pair(x, y)); st.push(step); } } } } } int best_len = -1; string best_path = ""; string short_path = ""; vector<vector<string> > paths; string path(int x, int y) { string& ret = paths[x][y]; if (ret != "") return ret; if (x == ti && y == tj) { ret = "T"; return ret; } int fd = f[x][y]; string tmp = ""; for (int k = 0; k < 4; ++k) { int xx = x + d[k][0]; int yy = y + d[k][1]; if (0 <= xx && xx < n && 0 <= yy && yy < m && f[xx][yy] == f[x][y] + 1) { string r = path(xx, yy); if (r != "X" && (tmp == "" || r < tmp)) tmp = r; } } if (tmp == "") ret = "X"; else { char c = ((x == si && y == sj) ? 'S' : (a[x][y] + 'a')); ret = c + tmp; } return ret; } vector<int> ch; vector<vector<int> > comb; vector<string> scomb; void combination(int pos, int len, vector<int> v) { if (len == 0) comb.push_back(v); if (len == 0 || len > pos + 1) return; combination(pos - 1, len, v); v.push_back(ch[pos]); combination(pos - 1, len - 1, v); } int main() { int k; cin >> n >> m >> k; if (n * m == 2) { cout << endl; return 0; } a = vector<vector<int> >(n, vector<int>(m, 0)); paths.resize(n, vector<string>(m, "")); vector<vector<string> > old = paths; for (int i = 0; i < n; ++i) { string s; cin >> s; for (int j = 0; j < m; ++j) { if (s[j] == 'S') { si = i; sj = j; a[i][j] = -1; } else if (s[j] == 'T') { ti = i; tj = j; a[i][j] = -2; } else { a[i][j] = s[j] - 'a'; ch.push_back(a[i][j]); } } } sort(ch.begin(), ch.end()); ch.resize(unique(ch.begin(), ch.end()) - ch.begin()); k = min(k, (int)ch.size()); combination(ch.size() - 1, k, vector<int>()); for (int i = 0; i < comb.size(); ++i) { string s = ""; for (int j = 0; j < comb[i].size(); ++j) s += (comb[i][j] + 'a'); sort(s.begin(), s.end()); scomb.push_back(s); } vector<int> pw(26, 0); for (int i = 0; i < 26; ++i) pw[i] = (1 << i); for (int i = 0; i < comb.size(); ++i) { c1 = c2 = c3 = c4 = -100; int sz = comb[i].size(); c1 = comb[i][0]; if (sz > 1) c2 = comb[i][1]; if (sz > 2) c3 = comb[i][2]; if (sz > 3) c4 = comb[i][3]; memset(f, 0, sizeof(f)); go(); if (f[ti][tj] == 0) continue; if (best_len != -1 && f[ti][tj] > best_len) continue; if (f[ti][tj] == best_len) if (*short_path.rbegin() <= scomb[i][0]) continue; paths = old; path(si, sj); string& cand = paths[si][sj]; if ((best_len == -1 || cand.size() < best_len) || (cand.size() == best_len && cand < best_path)) { best_len = cand.size(); best_path = cand; cand = string(cand.begin() + 1, cand.end() - 1); sort(cand.begin(), cand.end()); cand.resize(unique(cand.begin(), cand.end()) - cand.begin()); short_path = cand; } } if (best_len == -1) cout << -1 << endl; else { string& s = best_path; cout << string(s.begin() + 1, s.end() - 1) << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 55; int n, m, K, sx, sy, ex, ey; char s[N][N]; vector<char> has; vector<int> ok; bool fd = false; string ans; int len = 1 << 20; pair<int, int> pre[N][N]; int rk[N][N]; bool O[300]; const int inf = 1 << 30; bool Cmp(const pair<int, int>& a, const pair<int, int>& b) { if (rk[a.first][a.second] != rk[b.first][b.second]) return rk[a.first][a.second] < rk[b.first][b.second]; return s[a.first][a.second] < s[b.first][b.second]; } bool same(const pair<int, int>& a, const pair<int, int>& b) { return s[a.first][a.second] == s[b.first][b.second] && rk[a.first][a.second] == rk[b.first][b.second]; } int tmp[N * N]; void solve() { for (int i = 0; i < n; ++i) for (int j = 0; j < m; ++j) rk[i][j] = inf; vector<pair<int, int> > Q; Q.push_back(make_pair(sx, sy)); rk[sx][sy] = 0; for (int i = 0; i < (int)(ok).size(); ++i) O[ok[i]] = true; int L = 0; O[(int)'T'] = true; while ((int)(Q).size()) { vector<pair<int, int> > P; for (int i = 0; i < (int)(Q).size(); ++i) { int x = Q[i].first, y = Q[i].second; for (int d = 0; d < 4; ++d) { int nx = x + (d == 2) - (d == 0); int ny = y + (d == 3) - (d == 1); if (0 <= nx && nx < n && 0 <= ny && ny < m && O[(int)s[nx][ny]] && rk[nx][ny] > rk[x][y]) { if (rk[nx][ny] == inf) P.push_back(make_pair(nx, ny)); rk[nx][ny] = rk[x][y]; pre[nx][ny] = make_pair(x, y); } } } sort((P).begin(), (P).end(), Cmp); tmp[0] = ++L; for (int i = 1; i < (int)(P).size(); ++i) tmp[i] = same(P[i], P[i - 1]) ? tmp[i - 1] : ++L; for (int i = 0; i < (int)(P).size(); ++i) rk[P[i].first][P[i].second] = tmp[i]; swap(Q, P); } for (int i = 0; i < (int)(ok).size(); ++i) O[ok[i]] = false; if (rk[ex][ey] == inf) return; fd = true; string S; for (int i = ex, j = ey; i != sx || j != sy;) { S += s[i][j]; int ni = pre[i][j].first, nj = pre[i][j].second; i = ni, j = nj; } reverse((S).begin(), (S).end()); S.pop_back(); if ((int)(S).size() < len) len = (int)(S).size(), ans = S; else if ((int)(S).size() == len) ans = min(ans, S); } void dfs(int c, int k) { if (k > K) return; if (c == (int)(has).size()) { solve(); return; } dfs(c + 1, k); ok.push_back(has[c]); dfs(c + 1, k + 1); ok.pop_back(); } int main() { scanf("%d%d%d", &n, &m, &K); for (int i = 0; i < n; ++i) scanf("%s", s[i]); for (int i = 0; i < n; ++i) for (int j = 0; j < m; ++j) { if (s[i][j] == 'S') sx = i, sy = j; else if (s[i][j] == 'T') ex = i, ey = j; else has.push_back(s[i][j]); } sort((has).begin(), (has).end()); has.erase(unique((has).begin(), (has).end()), has.end()); dfs(0, 0); if (!fd) puts("-1"); else printf("%s\n", ans.c_str()); return 0; }
#include <bits/stdc++.h> using namespace std; int n, m, k, can[256], fx, fy, sx, sy; int d[] = {0, 1, 1, 0, -1, 0, 0, -1}; int a[70][70], ans = (1 << 30); char Map[70][70]; bool u[70][70]; queue<int> qx, qy, Qx[2], Qy[2]; string strans, str; bool check(int x, int y) { return x >= 0 && x < n && y >= 0 && y < m; } void path(int steps) { str = ""; steps--; int x, y, dx, dy, mn; char want; Qx[steps & 1].push(sx); Qy[steps & 1].push(sy); for (; steps >= 0; steps--) { queue<int> &qX = Qx[steps & 1], &qY = Qy[steps & 1], &nx = Qx[(steps + 1) & 1], &ny = Qy[(steps + 1) & 1]; want = 'z' + 1; memset(u, 0, sizeof u); while (!qX.empty()) { x = qX.front(); y = qY.front(); qX.pop(); qY.pop(); for (int i = 0; i < 8; i += 2) { dx = x + d[i]; dy = y + d[i + 1]; if (!check(dx, dy)) continue; if (a[dx][dy] != a[x][y] - 1) continue; if (Map[dx][dy] < want) { while (!nx.empty()) nx.pop(), ny.pop(); want = Map[dx][dy]; } if (Map[dx][dy] == want && !u[dx][dy]) nx.push(dx), ny.push(dy), u[dx][dy] = 1; } } if (want == 'T') break; str.push_back(want); } } void solve() { int x, y, dx, dy; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { a[i][j] = (1 << 30); } } qx.push(fx); qy.push(fy); a[fx][fy] = 0; while (!qx.empty()) { x = qx.front(); y = qy.front(); qx.pop(); qy.pop(); for (int i = 0; i < 8; i += 2) { dx = x + d[i]; dy = y + d[i + 1]; if (check(dx, dy) && a[dx][dy] > a[x][y] + 1 && can[Map[dx][dy]]) { a[dx][dy] = a[x][y] + 1; qx.push(dx); qy.push(dy); } } } if (a[sx][sy] == (1 << 30)) return; if (a[sx][sy] < ans) { ans = a[sx][sy]; path(a[sx][sy]); strans = str; } else if (a[sx][sy] == ans) { path(a[sx][sy]); if (str < strans) strans = str; } } void rec(int d, int i = 0) { if (d == k) { solve(); return; } for (; i < 27; i++) { can['a' + i] = 1; rec(d + 1, i + 1); can['a' + i] = 0; } } int main() { scanf("%d%d%d", &n, &m, &k); for (int i = 0; i < n; i++) { scanf("%s", Map[i]); for (int j = 0; j < m; j++) { if (Map[i][j] == 'S') sx = i, sy = j; if (Map[i][j] == 'T') fx = i, fy = j; } } can['S'] = can['T'] = 1; rec(0); if (ans < (1 << 30)) printf("%s\n", strans.c_str()); else printf("-1\n"); return 0; }
#include <bits/stdc++.h> using namespace std; template <typename T> void out(T res) { cout << res << endl; exit(0); } string a[55]; int n, m, k, st, fn; bool allowed[26]; int way[55][55]; int dist[55][55]; int dr[] = {+1, 0, -1, 0}; int dc[] = {0, +1, 0, -1}; bool inBounds(int r, int c) { return (0 <= r && r < n && 0 <= c && c < m); } bool Check(int r, int c) { return inBounds(r, c) && (a[r][c] == 'S' || a[r][c] == 'T' || allowed[a[r][c] - 'a']); } string getWay(char c1, char c2, char c3, char c4) { memset(dist, -1, sizeof(dist)); dist[fn / m][fn % m] = 0; queue<int> q; q.push(fn); while (!q.empty()) { int r = q.front() / m; int c = q.front() % m; q.pop(); int nr, nc; for (int p = (0), _b(4); p < _b; p++) if (Check(nr = r + dr[p], nc = c + dc[p])) { if (dist[nr][nc] != -1) continue; dist[nr][nc] = dist[r][c] + 1; q.push(nr * m + nc); } } if (dist[st / m][st % m] == -1) return "-1"; vector<int> v; v.push_back(st); string res = ""; for (int i = (1), _b(dist[st / m][st % m]); i < _b; i++) { int nr, nc; int mm = 26; for (int j = (0), _b((int)(v).size()); j < _b; j++) for (int p = (0), _b(4); p < _b; p++) if (Check(nr = v[j] / m + dr[p], nc = v[j] % m + dc[p])) if (dist[nr][nc] == dist[st / m][st % m] - i) mm = min(mm, a[nr][nc] - 'a'); res += (mm + 'a'); vector<int> add; for (int j = (0), _b((int)(v).size()); j < _b; j++) for (int p = (0), _b(4); p < _b; p++) if (Check(nr = v[j] / m + dr[p], nc = v[j] % m + dc[p])) if (dist[nr][nc] == dist[st / m][st % m] - i) if (a[nr][nc] - 'a' == mm) add.push_back(nr * m + nc); v.clear(); for (int j = (0), _b((int)(add).size()); j < _b; j++) v.push_back(add[j]); sort(v.begin(), v.end()); v.erase(unique(v.begin(), v.end()), v.end()); } return res; } int main() { cin >> n >> m >> k; for (int i = (0), _b(n); i < _b; i++) cin >> a[i]; for (int i = (0), _b(n); i < _b; i++) for (int j = (0), _b(m); j < _b; j++) { if (a[i][j] == 'S') st = i * m + j; if (a[i][j] == 'T') fn = i * m + j; } string res = "-1"; for (int c1 = (0), _b(26); c1 < _b; c1++) for (int c2 = (c1), _b(26); c2 < _b; c2++) for (int c3 = (c2), _b(26); c3 < _b; c3++) for (int c4 = (c3), _b(26); c4 < _b; c4++) { if (k > 0) allowed[c1] = true; if (k > 1) allowed[c2] = true; if (k > 2) allowed[c3] = true; if (k > 3) allowed[c4] = true; string curr = getWay(c1, c2, c3, c4); if (curr != "-1") if (res == "-1" || (int)(res).size() > (int)(curr).size() || ((int)(res).size() == (int)(curr).size() && res > curr)) res = curr; allowed[c1] = allowed[c2] = allowed[c3] = allowed[c4] = false; } out(res); return 0; }
#include <bits/stdc++.h> using namespace std; struct node { int x, y, msk; string s; node(int x1, int x2, int x3, string x4) { x = x1, y = x2, msk = x3, s = x4; } bool operator<(const node &b) const { if (s.size() != b.s.size()) return s.size() > b.s.size(); return s > b.s; } }; int gx[5] = {0, 1, 0, -1, 0}, gy[5] = {0, 0, 1, 0, -1}; char s[51][51]; set<int> st[51][51]; int las[51][51]; int count(int x) { int ans = 0; while (x) ans += x & 1, x >>= 1; return ans; } signed main() { int x = 0, y = 0; int n, m, k; scanf("%d%d%d", &n, &m, &k); for (int i = 1; i <= n; i++) cin >> s[i] + 1; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) if (s[i][j] == 'S') x = i, y = j; priority_queue<node> q; q.push(node(x, y, 0, "")); while (!q.empty()) { node u = q.top(); q.pop(); for (int i = 1; i <= 4; i++) { int tox = u.x + gx[i]; int toy = u.y + gy[i]; if (tox > n || toy > m || tox <= 0 || toy <= 0) continue; if (s[tox][toy] == 'T') { cout << u.s; return 0; } int mk = u.msk | (1 << (s[tox][toy] - 'a')); if (count(mk) > k) continue; if (las[tox][toy] && ((las[tox][toy] & mk) == las[tox][toy])) continue; las[tox][toy] = mk; if (st[tox][toy].count(mk)) continue; st[tox][toy].insert(mk); string tmp = u.s; q.push(node(tox, toy, mk, u.s + s[tox][toy])); } } printf("-1"); return 0; }
#include <bits/stdc++.h> using namespace std; const int Inf = 1000000000; const int Maxn = 50; const int Maxl = 26; const int Maxd = 4; const int dy[Maxd] = {1, 0, -1, 0}; const int dx[Maxd] = {0, 1, 0, -1}; int n, m, k; char B[Maxn][Maxn]; int sx, sy, ex, ey; int has[Maxl]; int dist[Maxn][Maxn]; pair<int, int> p[Maxn][Maxn]; string s, res; bool sol; void BFS() { fill((int *)dist, (int *)dist + Maxn * Maxn, Inf); pair<int, int> v = make_pair(ex, ey); dist[v.first][v.second] = 0; vector<pair<int, int> > seq, buck[Maxl]; seq.push_back(v); for (int i = 0; !seq.empty(); i++) { for (int j = 0; j < seq.size(); j++) { v = seq[j]; for (int d = 0; d < Maxd; d++) { int ni = v.first + dy[d], nj = v.second + dx[d]; if (0 <= ni && ni < n && 0 <= nj && nj < m && i + 1 < dist[ni][nj] && (B[ni][nj] == 'S' || has[B[ni][nj] - 'a'])) { dist[ni][nj] = i + 1; p[ni][nj] = make_pair(v.first, v.second); if (B[ni][nj] == 'S') return; else buck[B[ni][nj] - 'a'].push_back(make_pair(ni, nj)); } } } seq.clear(); for (int j = 0; j < Maxl; j++) { for (int l = 0; l < buck[j].size(); l++) seq.push_back(buck[j][l]); buck[j].clear(); } } } void getPath(string &s) { s = ""; pair<int, int> v = p[sx][sy]; while (v.first != ex || v.second != ey) { s += B[v.first][v.second]; v = p[v.first][v.second]; } } void Search(int v, int from) { if (v == k) { BFS(); if (dist[sx][sy] == Inf) return; getPath(s); if (!sol || s.length() < res.length() || s.length() == res.length() && s < res) res = s; sol = true; } else for (int i = from; i < Maxl; i++) { has[i] = true; Search(v + 1, i + 1); has[i] = false; } } int main() { scanf("%d %d %d", &n, &m, &k); for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { scanf(" %c", &B[i][j]); if (B[i][j] == 'S') { sx = i; sy = j; } else if (B[i][j] == 'T') { ex = i; ey = j; B[i][j] = 'a'; } } Search(0, 0); if (!sol) printf("-1\n"); else printf("%s\n", res.c_str()); return 0; }
#include <bits/stdc++.h> using namespace std; char field[50][50]; bool used[50][50]; int n, m, k; int counts[26]; int cur_set; set<string> min_ways; int min_len = INT_MAX; int start_x, start_y, end_x, end_y; vector<char> alpha(0); bool comp(pair<int, int> a, pair<int, int> b) { if (field[a.first][a.second] == 'T') return true; if (field[b.first][b.second] == 'T') return false; return field[a.first][a.second] < field[b.first][b.second]; } vector<pair<int, int>> find_near(int from_y, int from_x, const set<char> &from_set) { vector<pair<int, int>> near(0); if (from_y > 0 && !used[from_y - 1][from_x] && from_set.find(field[from_y - 1][from_x]) != from_set.end()) near.push_back(make_pair(from_y - 1, from_x)); if (from_y < n - 1 && !used[from_y + 1][from_x] && from_set.find(field[from_y + 1][from_x]) != from_set.end()) near.push_back(make_pair(from_y + 1, from_x)); if (from_x > 0 && !used[from_y][from_x - 1] && from_set.find(field[from_y][from_x - 1]) != from_set.end()) near.push_back(make_pair(from_y, from_x - 1)); if (from_x < m - 1 && !used[from_y][from_x + 1] && from_set.find(field[from_y][from_x + 1]) != from_set.end()) near.push_back(make_pair(from_y, from_x + 1)); sort(near.begin(), near.end(), comp); return near; } set<char> find_set_near(int from_y, int from_x) { set<char> near = set<char>(); if (from_y > 0 && !used[from_y - 1][from_x]) near.insert(field[from_y - 1][from_x]); if (from_y < n - 1 && !used[from_y + 1][from_x]) near.insert(field[from_y + 1][from_x]); if (from_x > 0 && !used[from_y][from_x - 1]) near.insert(field[from_y][from_x - 1]); if (from_x < m - 1 && !used[from_y][from_x + 1]) near.insert(field[from_y][from_x + 1]); near.erase('T'); near.erase('S'); return near; } set<char> find_second_near_set(int from_y, int from_x, set<char> &not_from) { bool l2, l1, r1, r2, u1, u2, d1, d2; l2 = from_x - 2 >= 0; l1 = from_x > 0; r1 = from_x + 2 < m; r2 = from_x + 1 < m; u2 = from_y - 2 >= 0; u1 = from_y > 0; d1 = from_y + 1 < n; d2 = from_y + 2 < n; int yu2 = from_y - 2; int yu1 = from_y - 1; int yd1 = from_y + 1; int yd2 = from_y + 2; int xl2 = from_x - 2; int xl1 = from_x - 1; int xr1 = from_x + 1; int xr2 = from_x + 2; set<char> ret = set<char>(); if (l1 && u2) ret.insert(field[yu2][xl1]); if (u2) ret.insert(field[yu2][from_x]); if (u2 && r1) ret.insert(field[yu2][xr1]); if (r2) { if (u1) ret.insert(field[yu1][xr2]); ret.insert(field[from_y][xr2]); if (d1) ret.insert(field[yd1][xr2]); } if (d2) { if (r1) ret.insert(field[yd2][xr1]); ret.insert(field[yd2][from_x]); if (l1) ret.insert(field[yd2][xl1]); } if (l2) { if (d1) ret.insert(field[yd1][xl2]); ret.insert(field[from_y][xl2]); if (u1) ret.insert(field[yu1][xl2]); } for (set<char>::iterator i = not_from.begin(); i != not_from.end(); i++) ret.erase(*i); return ret; } void read() { set<char> set_alpha = set<char>(); cin >> n >> m >> k; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { cin >> field[i][j]; if (field[i][j] == 'S') { start_y = i; start_x = j; } else if (field[i][j] == 'T') { end_y = i; end_x = j; } else set_alpha.insert(field[i][j]); } for (set<char>::iterator i = set_alpha.begin(); i != set_alpha.end(); i++) alpha.push_back(*i); } struct cell { pair<int, int> pos; string s; }; struct comp2 { bool operator()(const cell &a, const cell &b) { if (a.s.size() != b.s.size()) return a.s.size() < b.s.size(); else return a.s < b.s; } }; set<set<char>> last_sets; bool wave(set<char> &cur_set) { if (last_sets.find(cur_set) != last_sets.end()) return false; else last_sets.insert(cur_set); memset(used, false, 2500); used[start_y][start_x] = true; cur_set.insert('T'); multiset<cell, comp2> myque; cell tmp; tmp.pos = make_pair(start_y, start_x); tmp.s = string(""); myque.insert(tmp); while (!myque.empty()) { cell cur_cell = *myque.begin(); myque.erase(myque.begin()); if (cur_cell.s.length() > min_len) break; vector<pair<int, int>> near = find_near(cur_cell.pos.first, cur_cell.pos.second, cur_set); for (vector<pair<int, int>>::iterator i = near.begin(); i != near.end(); i++) { if (field[i->first][i->second] == 'T') { if (cur_cell.s.length() < min_len) { min_ways.clear(); min_len = cur_cell.s.length(); } min_ways.insert(cur_cell.s); break; } used[i->first][i->second] = true; cell tmp = cur_cell; tmp.pos = *i; tmp.s.push_back(field[i->first][i->second]); myque.insert(tmp); } } cur_set.erase('T'); return false; } int main() { read(); string s(""); set<char> start_set = find_set_near(start_y, start_x); set<char> end_set = find_set_near(end_y, end_x); int l = alpha.size(); set<char> cur_set = set<char>(); if (!l) wave(cur_set); else { for (set<char>::iterator a = start_set.begin(); a != start_set.end(); a++) { cur_set.insert(*a); if (cur_set.size() == k || l < k && cur_set.size() == l) wave(cur_set); else { for (set<char>::iterator b = end_set.begin(); b != end_set.end(); b++) { cur_set.insert(*b); if (cur_set.size() == k || l < k && cur_set.size() == l) wave(cur_set); else { for (int i = 0; i < l; i++) { if (cur_set.end() != cur_set.find(alpha[i])) continue; cur_set.insert(alpha[i]); if (cur_set.size() == k || l < k && cur_set.size() == l) wave(cur_set); else { for (int j = i + 1; j < l; j++) { if (cur_set.end() != cur_set.find(alpha[j])) continue; cur_set.insert(alpha[j]); if ((*a) == (*b) && cur_set.size() < k) { set<char> second_set = find_second_near_set(start_y, start_x, cur_set); if (!second_set.size()) wave(cur_set); else { for (set<char>::iterator p = second_set.begin(); p != second_set.end(); p++) { cur_set.insert(*p); wave(cur_set); cur_set.erase(*p); } } } else wave(cur_set); cur_set.erase(alpha[j]); } } cur_set.erase(alpha[i]); } } cur_set.erase(*b); } } cur_set.erase(*a); } } label_end: if (min_len == INT_MAX) cout << "-1"; else cout << (*min_ways.begin()); }
#include <bits/stdc++.h> using namespace std; int R, C, K, Tail; int Board[60][60], Road[60][60], Best[60][60], Oki[60][60]; int Allow[100000][5]; int Last[60][60]; char Now[5]; int Res; int Check[30]; char Ans[10000]; int QR[10000], QC[10000]; void pre_process(char now, int left) { if (now > 'z') { if (left == 0) { int i; for (i = 0; i < (int)(K); i++) Allow[Tail][i] = (int)(Now[i] - 'a'); Tail++; } return; } pre_process(now + 1, left); if (left > 0) { Now[left - 1] = now; pre_process(now + 1, left - 1); } } bool isValid(int r, int c) { return 0 <= r && r < R && 0 <= c && c < C && Road[r][c]; } int main() { int i, j, k, r, c; int sr, sc, er, ec; char a; int dr[4] = {-1, 0, 1, 0}; int dc[4] = {0, 1, 0, -1}; int tt, et; scanf("%d%d%d", &R, &C, &K); for (i = 0; i < (int)(R); i++) { for (j = 0; j < (int)(C); j++) { scanf("%c", &a); if (!('a' <= a && a <= 'z') && a != 'S' && a != 'T') { j--; continue; } if ('a' <= a && a <= 'z') Board[i][j] = a - 'a'; else if (a == 'S') Board[i][j] = -1, sr = i, sc = j; else Board[i][j] = -2, er = i, ec = j; } } Tail = 0; pre_process('a', K); Res = -1; for (i = 0; i < (int)(Tail); i++) { for (j = 0; j < (int)(26); j++) Check[j] = 0; for (j = 0; j < (int)(K); j++) Check[Allow[i][j]] = 1; for (r = 0; r < (int)(R); r++) for (c = 0; c < (int)(C); c++) { if (Board[r][c] >= 0) Road[r][c] = Check[Board[r][c]]; else Road[r][c] = 1; Best[r][c] = -1; Oki[r][c] = 0; Last[r][c] = 0; } tt = 1; QR[0] = sr, QC[0] = sc; Best[sr][sc] = 0; for (j = 0; j < (int)(tt); j++) { r = QR[j], c = QC[j]; for (k = 0; k < (int)(4); k++) if (isValid(r + dr[k], c + dc[k]) && Best[r + dr[k]][c + dc[k]] == -1) { Best[r + dr[k]][c + dc[k]] = Best[r][c] + 1; QR[tt] = r + dr[k], QC[tt] = c + dc[k]; tt++; } } if (Best[er][ec] == -1 || (Res != -1 && Best[er][ec] > Res)) continue; bool update = false; if (Res == -1 || Best[er][ec] < Res) update = true; Res = Best[er][ec]; Ans[Res - 1] = Ans[Res] = 0; tt = 1; QR[0] = er, QC[0] = ec; Oki[er][ec] = 1; for (j = 0; j < (int)(tt); j++) { r = QR[j], c = QC[j]; for (k = 0; k < (int)(4); k++) if (isValid(r + dr[k], c + dc[k]) && Best[r + dr[k]][c + dc[k]] == Best[r][c] - 1 && !Oki[r + dr[k]][c + dc[k]]) { Oki[r + dr[k]][c + dc[k]] = 1; QR[tt] = r + dr[k], QC[tt] = c + dc[k]; tt++; } } int cur = 0, tt = 1, move = 0; QR[0] = sr, QC[0] = sc; Best[sr][sc] = 0; while (cur < Res - 1) { et = tt; int best = -1; for (j = move; j < et; j++) { r = QR[j], c = QC[j]; for (k = 0; k < (int)(4); k++) if (isValid(r + dr[k], c + dc[k]) && Oki[r + dr[k]][c + dc[k]] && Best[r + dr[k]][c + dc[k]] == cur + 1) { if (best == -1 || best > Board[r + dr[k]][c + dc[k]]) { best = Board[r + dr[k]][c + dc[k]]; } } } if (!update && (char)(best + 'a') > Ans[cur]) break; if (!update && (char)(best + 'a') < Ans[cur]) update = true; Ans[cur] = (char)(best + 'a'); cur++; for (j = move; j < et; j++) { r = QR[j], c = QC[j]; for (k = 0; k < (int)(4); k++) if (isValid(r + dr[k], c + dc[k]) && Oki[r + dr[k]][c + dc[k]] && Best[r + dr[k]][c + dc[k]] == cur && !Last[r + dr[k]][c + dc[k]]) { if (best == Board[r + dr[k]][c + dc[k]]) { Last[r + dr[k]][c + dc[k]] = 1; QR[tt] = r + dr[k], QC[tt] = c + dc[k]; tt++; } } } move = et; } } if (Res == -1) printf("%d\n", Res); else printf("%s\n", Ans); return 0; }
#include <bits/stdc++.h> using namespace std; queue<pair<int, int> > q; string s, jwb; pair<int, int> u, aw, ak; int r, c, bts, a, h, mi, ni, nj, ui, uj; char sc[55][55]; int boleh[27]; string kjg[55][55]; int ari[4] = {-1, 0, 1, 0}; int arj[4] = {0, 1, 0, -1}; int main() { scanf("%d%d%d", &r, &c, &bts); for (int i = 0; i < r; i++) { scanf("%s", sc[i]); for (int j = 0; j < c; j++) { if (sc[i][j] == 'S') { aw = make_pair(i, j); } if (sc[i][j] == 'T') { ak = make_pair(i, j); } } } for (int i = 0; i < 26; i++) { boleh[i] = 1; } for (int i = 0; i < bts; i++) { boleh[i] = 0; } jwb = ""; mi = 2123123123; do { for (int i = 0; i < r; i++) { for (int j = 0; j < c; j++) { kjg[i][j] = ""; } } q.push(aw); while (!q.empty()) { ui = q.front().first; uj = q.front().second; q.pop(); for (int k = 0; k < 4; k++) { ni = ui + ari[k]; nj = uj + arj[k]; if ((0 <= ni) && (ni < r) && (0 <= nj) && (nj < c) && (sc[ni][nj] != 'S')) { if (sc[ni][nj] == 'T') { if (kjg[ni][nj].size() == 0) { kjg[ni][nj] = kjg[ui][uj] + sc[ni][nj]; q.push(make_pair(ni, nj)); } else if ((kjg[ni][nj].size() == kjg[ui][uj].size() + 1) && (kjg[ni][nj] > kjg[ui][uj] + sc[ni][nj])) { kjg[ni][nj] = kjg[ui][uj] + sc[ni][nj]; } } else if (boleh[sc[ni][nj] - 'a'] == 0) { if (kjg[ni][nj].size() == 0) { kjg[ni][nj] = kjg[ui][uj] + sc[ni][nj]; q.push(make_pair(ni, nj)); } else if ((kjg[ni][nj].size() == kjg[ui][uj].size() + 1) && (kjg[ni][nj] > kjg[ui][uj] + sc[ni][nj])) { kjg[ni][nj] = kjg[ui][uj] + sc[ni][nj]; } } } } } if ((int)kjg[ak.first][ak.second].size() > 0) { kjg[ak.first][ak.second].erase(kjg[ak.first][ak.second].size() - 1, 1); if ((int)kjg[ak.first][ak.second].size() < mi) { mi = kjg[ak.first][ak.second].size(); jwb = kjg[ak.first][ak.second]; } else if ((int)kjg[ak.first][ak.second].size() == mi) { jwb = min(jwb, kjg[ak.first][ak.second]); } } } while (next_permutation(boleh, boleh + 26)); if (mi == 2123123123) { cout << -1 << endl; } else { cout << jwb << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; char tbl[60][60]; int n, m, k, sx, sy, gx, gy; void input() { scanf("%d%d%d", &n, &m, &k); for (int i = 0; i < n; i++) scanf("%s", tbl[i]); for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) if (tbl[i][j] == 'S') { sx = i; sy = j; } else if (tbl[i][j] == 'T') { gx = i; gy = j; } } const int dx[] = {1, 0, -1, 0}; const int dy[] = {0, 1, 0, -1}; bool ok[130]; int dis[60][60], vis[60][60], fx[60][60], fy[60][60]; inline bool valid(int x, int y) { return x >= 0 && x < n && y >= 0 && y < m && ok[(int)tbl[x][y]]; } bool cmp(int x1, int y1, int x2, int y2) { if (tbl[x1][y1] != tbl[x2][y2]) return tbl[x1][y1] < tbl[x2][y2]; if (x1 == y1 && x2 == y2) return 0; return cmp(fx[x1][y1], fy[x1][y1], fx[x2][y2], fy[x2][y2]); } string go(int a, int b, int c, int d) { static int tmt = 0; tmt++; ok[a] = ok[b] = ok[c] = ok[d] = 1; queue<int> q; vis[gx][gy] = tmt; dis[gx][gy] = 0; q.push(gx); q.push(gy); while (!q.empty()) { int x = q.front(); q.pop(); int y = q.front(); q.pop(); for (int i = 0; i < 4; i++) { int nx = x + dx[i]; int ny = y + dy[i]; if (!valid(nx, ny)) continue; if (vis[nx][ny] != tmt) { vis[nx][ny] = tmt; dis[nx][ny] = dis[x][y] + 1; fx[nx][ny] = x; fy[nx][ny] = y; q.push(nx); q.push(ny); } else if (dis[nx][ny] == dis[x][y] + 1) { if (cmp(x, y, fx[nx][ny], fy[nx][ny])) { fx[nx][ny] = x; fy[nx][ny] = y; } } } } ok[a] = ok[b] = ok[c] = ok[d] = 0; if (vis[sx][sy] != tmt) return "!"; else { string ret; int x = fx[sx][sy], y = fy[sx][sy], xx, yy; while (x != gx || y != gy) { ret += tbl[x][y]; xx = fx[x][y]; yy = fy[x][y]; x = xx; y = yy; } return ret; } } int len = 10000; string ans; void chk(int a, int b, int c, int d) { string now = go(a, b, c, d); if (now == "!") return; if ((int)now.size() < len || ((int)now.size() == len && now < ans)) { ans = now; len = now.size(); } } void solve() { for (int a = 'a'; a <= 'z'; a++) if (k == 1) chk(a, 0, 0, 0); else for (int b = a + 1; b <= 'z'; b++) if (k == 2) chk(a, b, 0, 0); else for (int c = b + 1; c <= 'z'; c++) if (k == 3) chk(a, b, c, 0); else for (int d = c + 1; d <= 'z'; d++) chk(a, b, c, d); if (len == 10000) puts("-1"); else printf("%s\n", ans.c_str()); } int main() { ok[(int)'S'] = ok[(int)'T'] = 1; input(); solve(); return 0; }
#include <bits/stdc++.h> using namespace std; char a[55][55]; int d[55][55]; char res[55 * 55], c[55 * 55]; int u[256]; int nr, nc; int dx[] = {-1, 1, 0, 0}; int dy[] = {0, 0, -1, 1}; int n, m; int ch(int x, int y) { return x >= 0 && y >= 0 && x < n && y < m; } struct pt { int x; int y; friend int operator<(pt a, pt b) { if (a.x != b.x) { return a.x < b.x; } return a.y < b.y; } }; set<pt> ss; pt p, p1, p2; queue<pt> q; pt b[55 * 55 * 5], bb[55 * 55 * 5]; int nb, nbb; int cmp(char a[55 * 55], char b[55 * 55]) { int i; for (i = 0; a[i] && b[i]; i++) { if (a[i] != b[i]) { return a[i] < b[i]; } } return 0; } int i, j, k, x, y, z, t, t1, mx, c1, c2, c3, c4, bx, by, ex, ey, r, l; int mn; int main() { scanf("%d%d%d", &n, &m, &mx); for (i = 0; i < n; i++) { scanf("%s", &a[i]); for (j = 0; j < m; j++) { if (a[i][j] == 'S') { bx = i; by = j; } if (a[i][j] == 'T') { ex = i; ey = j; } } } u['T'] = 1; u['S'] = 1; for (c1 = 'a'; c1 <= 'z'; c1++) { for (c2 = c1; c2 <= 'z'; c2++) { for (c3 = c2; c3 <= 'z'; c3++) { for (c4 = c3; c4 <= 'z'; c4++) { for (i = 'a'; i <= 'z'; i++) { u[i] = 0; } if (mx >= 1) { u[c1] = 1; } if (mx >= 2) { u[c2] = 1; } if (mx >= 3) { u[c3] = 1; } if (mx >= 4) { u[c4] = 1; } for (i = 0; i < n; i++) { for (j = 0; j < m; j++) { d[i][j] = -1; } } while (!q.empty()) q.pop(); p.x = ex; p.y = ey; d[p.x][p.y] = 0; q.push(p); while (!q.empty()) { p = q.front(); q.pop(); for (i = 0; i < 4; i++) { x = p.x + dx[i]; y = p.y + dy[i]; if (ch(x, y) && u[a[x][y]] == 1 && d[x][y] == -1) { d[x][y] = d[p.x][p.y] + 1; p1.x = x; p1.y = y; q.push(p1); } } } if (d[bx][by] == -1 || (d[bx][by] > nr && nr > 0)) { continue; } p.x = bx; p.y = by; nb = 0; b[nb++] = p; nc = d[bx][by]; for (l = 0; l < nc; l++) { nbb = 0; mn = 1000000; ss.clear(); for (i = 0; i < nb; i++) { for (j = 0; j < 4; j++) { x = b[i].x + dx[j]; y = b[i].y + dy[j]; if (ch(x, y) && d[x][y] == nc - l - 1) { if (a[x][y] < mn) { mn = a[x][y]; } } } } for (i = 0; i < nb; i++) { for (j = 0; j < 4; j++) { x = b[i].x + dx[j]; y = b[i].y + dy[j]; if (ch(x, y) && d[x][y] == nc - l - 1 && a[x][y] == mn) { p1.x = x; p1.y = y; if (ss.find(p1) == ss.end()) { bb[nbb++] = p1; ss.insert(p1); } } } } for (i = 0; i < nbb; i++) { b[i] = bb[i]; } nb = nbb; c[l] = mn; } c[nc] = 0; if (nc < nr || nr == 0 || cmp(c, res)) { nr = nc; for (i = 0; i < nc; i++) { res[i] = c[i]; } res[nr] = 0; } if (mx >= 4) { u[c4] = 0; } } if (mx >= 3) { u[c3] = 0; } } if (mx >= 2) { u[c2] = 0; } } u[c1] = 0; } if (nr == 0) { printf("-1\n"); return 0; } else { res[nr - 1] = 0; printf("%s\n", res); } return 0; }
#include <bits/stdc++.h> using namespace std; int SX, SY, TX, TY; int N, M, K; char V[52][52]; vector<vector<int> > C; vector<int> cur; void gen(int sv, int how) { if (sv >= 26 && cur.size() == K) C.push_back(cur); if (sv >= 26 || how < 0) return; gen(sv + 1, how); if (how > 0) { cur.push_back(sv); gen(sv + 1, how - 1); cur.pop_back(); } } int bestl = (int)1E9; string best; bool can[300]; int LEV[50][50]; deque<int> QX, QY; string dp[50][50]; string wrd; vector<int> PX, PY; vector<int> _PX, _PY; int u1[50][50], u1s = 0; string dfs(int x, int y) { PX.clear(); PY.clear(); wrd = ""; PX.push_back(x); PY.push_back(y); while (1) { ++u1s; if (PX[0] == TX && PY[0] == TY) return wrd; _PX.clear(); _PY.clear(); char USE = 'z' + 1; for (int i = 0; i < PX.size(); ++i) { x = PX[i]; y = PY[i]; if (x - 1 >= 0 && can[V[x - 1][y]] && LEV[x - 1][y] == LEV[x][y] - 1) USE = min(USE, V[x - 1][y]); if (y - 1 >= 0 && can[V[x][y - 1]] && LEV[x][y - 1] == LEV[x][y] - 1) USE = min(USE, V[x][y - 1]); if (x + 1 < N && can[V[x + 1][y]] && LEV[x + 1][y] == LEV[x][y] - 1) USE = min(USE, V[x + 1][y]); if (y + 1 < M && can[V[x][y + 1]] && LEV[x][y + 1] == LEV[x][y] - 1) USE = min(USE, V[x][y + 1]); } wrd += USE; for (int i = 0; i < PX.size(); ++i) { x = PX[i]; y = PY[i]; if (x - 1 >= 0 && can[V[x - 1][y]] && LEV[x - 1][y] == LEV[x][y] - 1 && USE == V[x - 1][y]) { if (u1[x - 1][y] != u1s) { _PX.push_back(x - 1); _PY.push_back(y); u1[x - 1][y] = u1s; } } if (y - 1 >= 0 && can[V[x][y - 1]] && LEV[x][y - 1] == LEV[x][y] - 1 && USE == V[x][y - 1]) { if (u1[x][y - 1] != u1s) { _PX.push_back(x); _PY.push_back(y - 1); u1[x][y - 1] = u1s; } } if (x + 1 < N && can[V[x + 1][y]] && LEV[x + 1][y] == LEV[x][y] - 1 && USE == V[x + 1][y]) { if (u1[x + 1][y] != u1s) { _PX.push_back(x + 1); _PY.push_back(y); u1[x + 1][y] = u1s; } } if (y + 1 < M && can[V[x][y + 1]] && LEV[x][y + 1] == LEV[x][y] - 1 && USE == V[x][y + 1]) { if (u1[x][y + 1] != u1s) { _PX.push_back(x); _PY.push_back(y + 1); u1[x][y + 1] = u1s; } } } PX = _PX; PY = _PY; } } string BFS(vector<int> U) { int i, j; for (i = 0; i < N; ++i) for (j = 0; j < M; ++j) dp[i][j].clear(); memset(LEV, -1, sizeof LEV); QX.clear(); QY.clear(); for (i = 0; i < U.size(); ++i) can[U[i] + 'a'] = true; can['S'] = can['T'] = true; LEV[TX][TY] = 1; QX.push_back(TX); QY.push_back(TY); while (!QX.empty()) { int x = QX[0], y = QY[0]; QX.pop_front(); QY.pop_front(); if (x - 1 >= 0 && can[V[x - 1][y]] && LEV[x - 1][y] == -1) { LEV[x - 1][y] = LEV[x][y] + 1; QX.push_back(x - 1); QY.push_back(y); } if (y - 1 >= 0 && can[V[x][y - 1]] && LEV[x][y - 1] == -1) { LEV[x][y - 1] = LEV[x][y] + 1; QX.push_back(x); QY.push_back(y - 1); } if (x + 1 < N && can[V[x + 1][y]] && LEV[x + 1][y] == -1) { LEV[x + 1][y] = LEV[x][y] + 1; QX.push_back(x + 1); QY.push_back(y); } if (y + 1 < M && can[V[x][y + 1]] && LEV[x][y + 1] == -1) { LEV[x][y + 1] = LEV[x][y] + 1; QX.push_back(x); QY.push_back(y + 1); } if (LEV[SX][SY] != -1) break; } string ret = "NO"; if (LEV[SX][SY] - LEV[TX][TY] - 1 <= bestl) if (LEV[SX][SY] != -1) { ret = dfs(SX, SY); ret = ret.substr(0, (int)ret.size() - 1); } for (i = 0; i < U.size(); ++i) can[U[i] + 'a'] = false; can['S'] = can['T'] = false; return ret; } bool IN[300]; int main() { int i, j, k, l, B = 0; scanf("%d%d%d", &N, &M, &K); for (i = 0; i < N; ++i) scanf("%s", &V[i]); for (i = 0; i < N; ++i) for (j = 0; j < M; ++j) { if (V[i][j] == 'S') { SX = i; SY = j; } else if (V[i][j] == 'T') { TX = i; TY = j; } else { if (!IN[V[i][j]]) ++B; IN[V[i][j]] = 1; } } K = min(K, B); gen(0, K); for (i = 0; i < C.size(); ++i) { bool OK = true; for (j = 0; j < C[i].size(); ++j) if (!IN['a' + C[i][j]]) { OK = false; break; } if (!OK) continue; string T = BFS(C[i]); if (T == "NO") continue; if (T.size() < bestl || (T.size() == bestl && T < best)) { best = T; bestl = best.size(); } } if (bestl > 1000000) cout << "-1\n"; else cout << best << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = (int)1e9; const long double EPS = 1e-9; const long double PI = 3.1415926535897932384626433832795; const int N = 100; const int dx[] = {0, 0, 1, -1}; const int dy[] = {1, -1, 0, 0}; int n, m, k; char a[N][N]; inline int sign(int a) { if (a == 0) return 0; return ((a < 0) ? (-1) : (1)); } int szchrs; char chrs[N * N]; pair<int, int> st, fn, sc; char tp[N]; bool isGood[300]; pair<int, int> bs, bt; inline bool good(const pair<int, int>& a) { return bs.first <= a.first && a.first < bt.first && bs.second <= a.second && a.second < bt.second; } int cu; int used[N][N]; int lvl[N][N], lvlT[N][N]; void updateAns(string& ans) { string res = ""; vector<pair<int, int> > cur; cur.push_back(sc); res.push_back(tp[0]); cu++; used[sc.first][sc.second] = cu; lvl[sc.first][sc.second] = 0; queue<pair<int, int> > q; q.push(sc); while (!q.empty()) { pair<int, int> v = q.front(); q.pop(); for (int i = 0; i < int(4); ++i) { pair<int, int> u(v.first + dx[i], v.second + dy[i]); if (good(u) && isGood[a[u.first][u.second]] && used[u.first][u.second] < cu) { used[u.first][u.second] = cu; lvl[u.first][u.second] = lvl[v.first][v.second] + 1; q.push(u); } } } if (used[fn.first][fn.second] < cu) return; cu++; used[fn.first][fn.second] = cu; lvlT[fn.first][fn.second] = 0; q.push(fn); while (!q.empty()) { pair<int, int> v = q.front(); q.pop(); for (int i = 0; i < int(4); ++i) { pair<int, int> u(v.first + dx[i], v.second + dy[i]); if (good(u) && isGood[a[u.first][u.second]] && used[u.first][u.second] < cu) { used[u.first][u.second] = cu; lvlT[u.first][u.second] = lvlT[v.first][v.second] + 1; q.push(u); } } } while (!cur.empty()) { char mn = 'z' + 1; for (int i = 0; i < int(int((cur).size())); ++i) for (int j = 0; j < int(4); ++j) { pair<int, int> nx(cur[i].first + dx[j], cur[i].second + dy[j]); if (good(nx) && used[nx.first][nx.second] == cu && lvl[nx.first][nx.second] + lvlT[nx.first][nx.second] == lvl[fn.first][fn.second] && lvl[nx.first][nx.second] == lvl[cur[i].first][cur[i].second] + 1) { mn = min(mn, a[nx.first][nx.second]); } } if (mn == 'z' + 1) throw; if (mn == 'T') { break; } else { res.push_back(mn); vector<pair<int, int> > c2; for (int i = 0; i < int(int((cur).size())); ++i) for (int j = 0; j < int(4); ++j) { pair<int, int> nx(cur[i].first + dx[j], cur[i].second + dy[j]); if (good(nx) && a[nx.first][nx.second] == mn && used[nx.first][nx.second] == cu && lvl[nx.first][nx.second] == lvl[cur[i].first][cur[i].second] + 1) { c2.push_back(nx); } } sort((c2).begin(), (c2).end()); c2.erase(unique((c2).begin(), (c2).end()), c2.end()); cur = c2; } } if (ans == "-1" || (int((ans).size()) > int((res).size()) || (int((ans).size()) == int((res).size()) && ans > res))) ans = res; } void solve(int cnt, int idx, string& ans) { if (cnt == k) { for (int j = 0; j < int(k); ++j) isGood[tp[j]] = true; updateAns(ans); for (int j = 0; j < int(k); ++j) isGood[tp[j]] = false; return; } for (int i = idx; i < szchrs; ++i) { tp[cnt] = chrs[i]; solve(cnt + 1, i, ans); } } int main() { cin >> n >> m >> k; for (int i = 0; i < int(n); ++i) for (int j = 0; j < int(m); ++j) { scanf(" %c", &a[i][j]); if (a[i][j] == 'S') { st = pair<int, int>(i, j); continue; } if (a[i][j] == 'T') { fn = pair<int, int>(i, j); continue; } chrs[szchrs++] = a[i][j]; } sort(chrs, chrs + szchrs); szchrs = unique(chrs, chrs + szchrs) - chrs; bs.first = 0; bs.second = 0; bt.first = n; bt.second = m; string ans = "-1"; isGood['S'] = true; isGood['T'] = true; for (int i = 0; i < int(4); ++i) { sc = pair<int, int>(st.first + dx[i], st.second + dy[i]); if (!good(sc)) continue; tp[0] = a[sc.first][sc.second]; if (tp[0] == 'T') { return 0; } solve(1, 0, ans); } cout << ans << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int dx[4] = {-1, 0, 1, 0}; const int dy[4] = {0, 1, 0, -1}; struct nd { int x, y, h; string s; nd(){}; nd(int x, int y, int h, string s) : x(x), y(y), h(h), s(s){}; bool operator<(const nd &oth) const { if (oth.s.length() != s.length()) return s.length() > oth.s.length(); return s > oth.s; } }; char a[55][55]; int n, m, mx; set<int> s[55][55]; int lst[55][55]; int bitcnt(int x) { int cnt = 0; for (int i = 0; i < 26; i++) if (x & (1 << i)) cnt++; return cnt; } bool dijk(int i, int j) { priority_queue<nd> pq; pq.push(nd(i, j, 0, "")); while (!pq.empty()) { nd cur = pq.top(); pq.pop(); for (int k = 0; k < 4; k++) { int x = cur.x + dx[k]; int y = cur.y + dy[k]; if (x < 0 || y < 0 || x >= n || y >= m) continue; if (a[x][y] == 'T') { cout << cur.s; return true; } int h = cur.h | (1 << (a[x][y] - 'a')); if (bitcnt(h) > mx || s[x][y].count(h)) continue; if (lst[x][y] && (lst[x][y] & h) == lst[x][y]) continue; lst[x][y] = h; s[x][y].insert(h); pq.push(nd(x, y, h, cur.s + a[x][y])); } } return false; } int main() { scanf("%d%d%d\n", &n, &m, &mx); for (int i = 0; i < n; i++) scanf("%s", a[i]); for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { if (a[i][j] == 'S') { if (!dijk(i, j)) printf("-1"); return 0; } } return 0; }
#include <bits/stdc++.h> int n, m, k; char mp[55][55], str[55 * 55]; int prei[55][55], prej[55][55], dis[55][55], vst[55][55]; int q2[2][55 * 55], r2[2], q[55 * 55]; int dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0}; bool used[55]; int res = 0x3f3f3f3f, si, ti, sj, tj; void solve() { memset(dis, 0x3f3f3f3f, sizeof(dis)); dis[ti][tj] = 0; int l = 0, r = 0; q[r++] = ti * m + tj; while (l != r) { int mask = q[l++]; int x = mask / m, y = mask % m; for (int i = 0; i < 4; ++i) { int nx = x + dx[i], ny = y + dy[i]; if (nx >= 0 && nx < n && ny >= 0 && ny < m && (mp[nx][ny] == 'S' || mp[nx][ny] == 'T' || used[mp[nx][ny] - 'a']) && dis[x][y] + 1 < dis[nx][ny]) { dis[nx][ny] = dis[x][y] + 1; q[r++] = nx * m + ny; } } } if (dis[si][sj] == 0x3f3f3f3f || dis[si][sj] > res) return; bool ok = false; if (dis[si][sj] < res) { ok = true; res = dis[si][sj]; } memset(vst, 0, sizeof(vst)); bool id = false; r2[id] = 0; q2[id][r2[id]++] = si * m + sj; for (int i = 0; i < dis[si][sj]; ++i) { id = !id; r2[id] = 0; char mini = 'z' + 1; for (int j = 0; j < r2[!id]; ++j) { int mask = q2[!id][j]; int x = mask / m, y = mask % m; if (mp[x][y] < mini) mini = mp[x][y]; } if (!ok && mini > str[i + 1]) return; if (mini < str[i + 1]) ok = true; str[i + 1] = mini; for (int j = 0; j < r2[!id]; ++j) { int mask = q2[!id][j]; int x = mask / m, y = mask % m; if (mp[x][y] == mini) { for (int h = 0; h < 4; ++h) { int nx = x + dx[h], ny = y + dy[h]; if (nx >= 0 && nx < n && ny >= 0 && ny < m && dis[x][y] - 1 == dis[nx][ny]) { if (vst[nx][ny] != i + 1) { vst[nx][ny] = i + 1; q2[id][r2[id]++] = nx * m + ny; } } } } } } } void dfs(int dep, int count) { if (dep == 26) { if (count == k) solve(); return; } dfs(dep + 1, count); if (count < k) { used[dep] = true; dfs(dep + 1, count + 1); used[dep] = false; } } int main() { scanf("%d%d%d", &n, &m, &k); for (int i = 0; i < n; ++i) { scanf("%s", mp[i]); for (int j = 0; j < m; ++j) if (mp[i][j] == 'S') si = i, sj = j; else if (mp[i][j] == 'T') ti = i, tj = j; } dfs(0, 0); if (res == 0x3f3f3f3f) puts("-1"); else { for (int i = 2; i <= res; ++i) putchar(str[i]); puts(""); } return 0; }
#include <bits/stdc++.h> using namespace std; int dx[] = {-1, 0, 1, 0}; int dy[] = {0, 1, 0, -1}; struct kraw { int a; bool jest; int kier; }; int main() { ios_base::sync_with_stdio(0); int n, m, k; cin >> n >> m >> k; vector<string> a(n); for (int i = 0; i < n; ++i) cin >> a[i]; vector<vector<kraw> > G(n * m); int start, meta; vector<char> lit(n * m); for (int i = 0; i < n; ++i) { for (int j = 0; j < m; ++j) { if (a[i][j] == 'S') start = i * m + j; if (a[i][j] == 'T') meta = i * m + j; lit[i * m + j] = a[i][j]; for (int l = 0; l < 4; ++l) { int x = i + dx[l], y = j + dy[l]; if (x >= 0 && x < n && y >= 0 && y < m) { G[i * m + j].push_back({x * m + y, true, 0}); G[x * m + y].push_back({i * m + j, true, 0}); } } } } string odp = ""; for (int mask = 0; mask < (1 << 26); ++mask) { if (__builtin_popcount(mask) != k) continue; for (int i = 0; i < n * m; ++i) { for (int j = 0; j < G[i].size(); ++j) { G[i][j].jest = true; G[i][j].kier = 0; } } for (int i = 0; i < n * m; ++i) for (int j = 0; j < G[i].size(); ++j) if ((lit[i] != 'S' && lit[i] != 'T' && (mask & (1 << (lit[i] - 'a'))) == 0) || (lit[G[i][j].a] != 'S' && lit[G[i][j].a] != 'T' && (mask & (1 << (lit[G[i][j].a] - 'a'))) == 0)) G[i][j].jest = false; queue<int> Q; vector<int> odl(n * m, -1); Q.push(start); odl[start] = 0; while (!Q.empty()) { int akt = Q.front(); Q.pop(); for (int i = 0; i < G[akt].size(); ++i) { if (G[akt][i].jest && odl[G[akt][i].a] == -1) { Q.push(G[akt][i].a); odl[G[akt][i].a] = odl[akt] + 1; } } } if (odl[meta] == -1) continue; for (int i = 0; i < n * m; ++i) { for (int j = 0; j < G[i].size(); ++j) { if (G[i][j].jest) { if (odl[i] == odl[G[i][j].a]) G[i][j].jest = false; if (odl[i] < odl[G[i][j].a]) G[i][j].kier = 1; if (odl[i] > odl[G[i][j].a]) G[i][j].kier = -1; } } } vector<int> st_wy(n * m, 0); for (int i = 0; i < n * m; ++i) for (int j = 0; j < G[i].size(); ++j) if (G[i][j].jest && G[i][j].kier == 1) ++st_wy[i]; for (int i = 0; i < n * m; ++i) if (st_wy[i] == 0) Q.push(i); while (!Q.empty()) { int akt = Q.front(); Q.pop(); if (akt == meta) continue; for (int i = 0; i < G[akt].size(); ++i) { if (G[akt][i].jest && G[akt][i].kier == -1) { int pop = G[akt][i].a; for (int j = 0; j < G[pop].size(); ++j) if (G[pop][j].a == akt && G[pop][j].jest) G[pop][j].jest = false; --st_wy[pop]; if (st_wy[pop] == 0) Q.push(pop); } } } string path = "S"; vector<int> a; a.push_back(start); while (path.size() < odl[meta]) { char l = 'z'; for (int i = 0; i < a.size(); ++i) for (int j = 0; j < G[a[i]].size(); ++j) if (G[a[i]][j].jest && G[a[i]][j].kier == 1) l = min(l, lit[G[a[i]][j].a]); path += l; vector<int> b; set<int> S; for (int i = 0; i < a.size(); ++i) { for (int j = 0; j < G[a[i]].size(); ++j) { if (G[a[i]][j].jest && G[a[i]][j].kier == 1 && lit[G[a[i]][j].a] == l && S.find(G[a[i]][j].a) == S.end()) { b.push_back(G[a[i]][j].a); S.insert(G[a[i]][j].a); } } } a = b; } path += "T"; if (odp == "" || (odp != "" && path.size() < odp.size()) || (odp != "" && path.size() == odp.size() && path < odp)) odp = path; } if (odp == "") cout << "-1"; else for (int i = 1; i < odp.size() - 1; ++i) cout << odp[i]; return 0; }
#include <bits/stdc++.h> using namespace std; string res = "-1", cur; const int dr[4] = {-1, 0, 1, 0}; const int dc[4] = {0, 1, 0, -1}; int R, C, k, sr, sc, tr, tc, q[100000], f, l, r, c, nr, nc, d; vector<int> p[50][50]; char s[50][51]; int cost[50][50]; bool in[27]; vector<int> push; void build() { q[f = l = 0] = tr; q[++l] = tc; cur = ""; while (f <= l) { char mn = 28; push.clear(); while (f <= l) { r = q[f]; ++f; c = q[f]; ++f; for (int i = 0; i < p[r][c].size(); ++i) { nr = r + dr[p[r][c][i]]; nc = c + dc[p[r][c][i]]; if (cost[nr][nc] == -1) continue; cost[nr][nc] = -1; if (s[nr][nc] < mn) { mn = s[nr][nc]; push.clear(); } if (s[nr][nc] == mn) { push.push_back(nr); push.push_back(nc); } } } if (mn == 26) break; cur += mn + 'a'; for (int i = 0; i < push.size(); ++i) q[++l] = push[i]; } if (res == "-1" || res.size() > cur.size() || res.size() == cur.size() && res > cur) res = cur; } void BFS() { for (int i = 0; i < R; ++i) for (int j = 0; j < C; ++j) { p[i][j].clear(); cost[i][j] = -1; } q[f = l = 0] = sr; q[++l] = sc; cost[sr][sc] = 0; while (f <= l) { r = q[f]; ++f; c = q[f]; ++f; if (r == tr && c == tc) { build(); return; } for (int i = 0; i < 4; ++i) { nr = r + dr[i]; nc = c + dc[i]; if (nr < 0 || nr == R || nc < 0 || nc == C || !in[s[nr][nc]]) continue; if (cost[nr][nc] == -1) { cost[nr][nc] = cost[r][c] + 1; p[nr][nc].push_back((i + 2) & 3); q[++l] = nr; q[++l] = nc; } else if (cost[nr][nc] == 1 + cost[r][c]) p[nr][nc].push_back((i + 2) & 3); } } } void calc(int i, int rem) { if (!rem) { BFS(); return; } if (i == 26) return; in[i] = true; calc(i + 1, rem - 1); in[i] = false; calc(i + 1, rem); } int main() { scanf("%d%d%d", &R, &C, &k); for (int i = 0; i < R; ++i) { scanf("%s", s[i]); for (int j = 0; j < C; ++j) if (s[i][j] == 'S') { tr = i; tc = j; s[i][j] = 26; } else if (s[i][j] == 'T') { sr = i; sc = j; s[i][j] = 26; } else s[i][j] -= 'a'; } in[26] = true; calc(0, k); puts(res.c_str()); return 0; }
#include <bits/stdc++.h> using namespace std; char str[52][52]; int road[52][52]; int n, m, k; int sx, sy, ex, ey; int able[52 * 52]; string bst; int sequence[52 * 52 * 8]; int afk[52][52]; int vis[52][52]; pair<int, int> pre[52][52]; int ax[] = {-1, 1, 0, 0}, ay[] = {0, 0, -1, 1}; void trysolve() { memset(vis, 0x3f, sizeof vis); memset(afk, 0x3f, sizeof afk); queue<pair<int, int> > q[2]; int now = 0; vis[sx][sy] = 1; q[now].push(make_pair(sx, sy)); afk[sx][sy] = 1; while (q[now].size() and vis[ex][ey] > 1e8) { vector<pair<int, int> > all; while (q[now].size()) { int x = q[now].front().first, y = q[now].front().second; q[now].pop(); for (int i = 0; i < 4; i++) { int tx = x + ax[i], ty = y + ay[i]; if (str[tx][ty] != 'T' and !able[road[tx][ty]]) continue; int ene = afk[x][y] * 5 + able[road[tx][ty]]; if (vis[tx][ty] > vis[x][y] + 1) { vis[tx][ty] = vis[x][y] + 1; afk[tx][ty] = ene; all.push_back(make_pair(tx, ty)); pre[tx][ty] = make_pair(x, y); } else if (vis[tx][ty] == vis[x][y] + 1 and afk[tx][ty] > ene) { afk[tx][ty] = ene; pre[tx][ty] = make_pair(x, y); } } } int upp = 0; for (int i = 0; i < all.size(); i++) sequence[afk[all[i].first][all[i].second]] = 1, upp = max(upp, afk[all[i].first][all[i].second]); int tot = 0; for (int i = 1; i <= upp; i++) if (sequence[i]) sequence[i] = ++tot; for (int i = 0; i < all.size(); i++) afk[all[i].first][all[i].second] = sequence[afk[all[i].first][all[i].second]]; for (int i = 1; i <= upp; i++) if (sequence[i]) sequence[i] = 0; now ^= 1; for (int i = 0; i < all.size(); i++) q[now].push(all[i]); } if (vis[ex][ey] < 1e8) { int x = pre[ex][ey].first, y = pre[ex][ey].second; string gg; while (x != sx or y != sy) { gg += char('a' - 1 + road[x][y]); pair<int, int> op = pre[x][y]; x = op.first, y = op.second; } reverse(gg.begin(), gg.end()); if (bst.size() > gg.size()) bst = gg; if (bst.size() == gg.size()) bst = min(bst, gg); } } void solve(int xk, int cnt) { if (cnt > k) return; if (xk == 27) trysolve(); if (xk == 27) return; solve(xk + 1, cnt); able[xk] = cnt + 1; solve(xk + 1, cnt + 1); able[xk] = 0; } signed main() { scanf("%d%d%d", &n, &m, &k); for (int i = 1; i <= n; i++) scanf("%s", str[i] + 1); for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) { if (str[i][j] == 'S') sx = i, sy = j; if (str[i][j] == 'T') ex = i, ey = j; bst += 'o'; } for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) road[i][j] = str[i][j] - 'a' + 1; solve(1, 0); if (bst.size() >= n * m) bst = "-1"; cout << bst; return 0; }
#include <bits/stdc++.h> #pragma comment(linker, "/STACK:10000000") using namespace std; template <typename T> inline T abs(T a) { return ((a < 0) ? -a : a); } template <typename T> inline T sqr(T a) { return a * a; } const int INF = (int)1E9 + 7; const long double EPS = 1E-9; const long double PI = 3.1415926535897932384626433832795; const int NMAX = 52; char a[NMAX][NMAX]; int n, m, k; pair<int, int> s, t; bool can[300]; const string FAIL = "$"; string ans = FAIL; void upd(const string& s) { if (s == FAIL) return; if (ans == FAIL) ans = s; else { if (int((ans).size()) > int((s).size()) || (int((ans).size()) == int((s).size()) && ans > s)) ans = s; } } int d1[NMAX][NMAX], d2[NMAX][NMAX]; const int dx[] = {0, 0, 1, -1}; const int dy[] = {1, -1, 0, 0}; inline bool in(const pair<int, int>& nv) { return !(nv.first < 0 || nv.first >= n || nv.second < 0 || nv.second >= m); } void genD(pair<int, int> s, int d[NMAX][NMAX]) { for (int i = 0; i < int(n); ++i) for (int j = 0; j < int(m); ++j) d[i][j] = INF; queue<pair<int, int> > q; q.push(s), d[s.first][s.second] = 0; while (!q.empty()) { pair<int, int> v = q.front(); q.pop(); for (int i = 0; i < int(4); ++i) { pair<int, int> nv(v.first + dx[i], v.second + dy[i]); if (!in(nv)) continue; if (!can[a[nv.first][nv.second]]) continue; if (d[nv.first][nv.second] > d[v.first][v.second] + 1) { d[nv.first][nv.second] = d[v.first][v.second] + 1; q.push(nv); } } } } string get() { genD(s, d1); genD(t, d2); if (d1[t.first][t.second] > INF / 2) return FAIL; string ans; vector<pair<int, int> > q; q.push_back(s); for (int step = 0; step < int(d1[t.first][t.second]); ++step) { vector<pair<int, int> > nq; char minC = -1; for (int i = 0; i < int(int((q).size())); ++i) { pair<int, int> v = q[i]; for (int j = 0; j < int(4); ++j) { pair<int, int> nv(v.first + dx[j], v.second + dy[j]); if (!in(nv) || !can[a[nv.first][nv.second]]) continue; if (d1[nv.first][nv.second] + d2[nv.first][nv.second] != d1[t.first][t.second]) continue; if (d1[nv.first][nv.second] <= d1[v.first][v.second]) continue; if (minC == -1) minC = a[nv.first][nv.second]; minC = min(minC, a[nv.first][nv.second]); } } ans += minC; for (int i = 0; i < int(int((q).size())); ++i) { pair<int, int> v = q[i]; for (int j = 0; j < int(4); ++j) { pair<int, int> nv(v.first + dx[j], v.second + dy[j]); if (!in(nv) || !can[a[nv.first][nv.second]]) continue; if (d1[nv.first][nv.second] + d2[nv.first][nv.second] != d1[t.first][t.second]) continue; if (d1[nv.first][nv.second] <= d1[v.first][v.second]) continue; if (a[nv.first][nv.second] != minC) continue; nq.push_back(nv); } } sort((nq).begin(), (nq).end()); nq.erase(unique((nq).begin(), (nq).end()), nq.end()); q = nq; } assert(int((q).size()) == 1 && q[0] == t); ans.erase(int((ans).size()) - 1); return ans; } void brute(char c, int cnt) { if (cnt > k) return; if (cnt == k) { upd(get()); return; } if (c > 'z') return; can[c] = true; brute(c + 1, cnt + 1); can[c] = false; brute(c + 1, cnt); } int main() { cin >> n >> m >> k; for (int i = 0; i < int(n); ++i) for (int j = 0; j < int(m); ++j) { scanf(" %c ", &a[i][j]); if (a[i][j] == 'S') s = pair<int, int>(i, j); if (a[i][j] == 'T') t = pair<int, int>(i, j); } can['S'] = true, can['T'] = true; brute('a', 0); if (ans == FAIL) puts("-1"); else cout << ans << endl; return 0; }
#include <bits/stdc++.h> using namespace std; struct Rohan { int x, y; int d, mask; string s; }; struct compare { bool operator()(Rohan a, Rohan b) { if (a.d == b.d) { return (a.s > b.s); } else { return (a.d > b.d); } } }; int distance(int x, int y, int a, int b) { return (abs(x - a) + abs(y - b)); } const int mx = 55; string a[mx]; int n, m, k, sx, sy, tx, ty; int dx[] = {0, 0, 1, -1}; int dy[] = {1, -1, 0, 0}; bool safe(int x, int y) { return (x >= 0 && x < n && y >= 0 && y < m && a[x][y] != 'S'); } int countBit(int n) { int ans = 0; while (n > 0) { int d = n % 2; n = n / 2; ans = ans + (d == 1); } return ans; } string bfs() { Rohan r = {sx, sy, distance(sx, sy, tx, ty), 0, ""}; priority_queue<Rohan, vector<Rohan>, compare> pq; set<pair<int, pair<int, int> > > s; pq.push(r); while (pq.empty() == false) { r = pq.top(); pq.pop(); if (a[r.x][r.y] == 'T') { return r.s; } if (s.find(make_pair(r.mask, make_pair(r.x, r.y))) != s.end()) { continue; } s.insert(make_pair(r.mask, make_pair(r.x, r.y))); for (int i = 0; i < 4; i++) { int row = r.x + dx[i]; int col = r.y + dy[i]; if (safe(row, col) == false) { continue; } if (row == tx && col == ty) { return r.s; } int next = r.mask | (1 << (a[row][col] - 97)); if (countBit(next) <= k) { Rohan temp; temp.x = row; temp.y = col; temp.s = r.s + a[row][col]; temp.d = distance(row, col, tx, ty) + r.s.length(); temp.mask = next; pq.push(temp); } } } return "-1"; } int main() { cin >> n >> m >> k; for (int i = 0; i < n; i++) { cin >> a[i]; } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (a[i][j] == 'S') { sx = i; sy = j; } else if (a[i][j] == 'T') { tx = i; ty = j; } } } cout << bfs(); return 0; }
#include <bits/stdc++.h> using namespace std; int dirx[4] = {-1, 0, 0, 1}; int diry[4] = {0, -1, 1, 0}; int qx[100001], head, tail, qy[100001]; int ena[100001], ech[100001]; int stx, sty, enx, eny; int res; char ress[3001], s[3001]; int n, m, k; char g[100][100]; int ans[3001]; int f[100][100]; int now; int vis[100][100]; inline void work() { now++; g[stx][sty] = ech[1]; qx[head = tail = 0] = enx, qy[0] = eny; memset(f, 63, sizeof(f)); f[enx][eny] = 0; while (head <= tail) { int x = qx[head], y = qy[head++]; for (int i = 0; i < 4; ++i) { int xx = x + dirx[i], yy = y + diry[i]; if (xx < 0 || yy < 0 || xx >= n || yy >= m || !ena[g[xx][yy]]) continue; if (f[xx][yy] > f[x][y] + 1) { f[xx][yy] = f[x][y] + 1; qx[++tail] = xx, qy[tail] = yy; } } } if (f[stx][sty] > res) return; memset(ans, 63, sizeof(ans)); ans[f[stx][sty]] = ech[1]; qx[head = tail = 0] = stx, qy[0] = sty; while (head <= tail) { int x = qx[head], y = qy[head++]; if (ans[f[x][y]] != g[x][y]) continue; for (int i = 0; i < 4; ++i) { int xx = x + dirx[i], yy = y + diry[i]; if (xx < 0 || yy < 0 || xx >= n || yy >= m || !ena[g[xx][yy]]) continue; if (f[xx][yy] == f[x][y] - 1 && vis[xx][yy] != now) { ans[f[xx][yy]] = ((ans[f[xx][yy]]) < (g[xx][yy]) ? (ans[f[xx][yy]]) : (g[xx][yy])); qx[++tail] = xx, qy[tail] = yy; vis[xx][yy] = now; } } } int sn = 0; for (int i = f[stx][sty] - 1; i > 0; --i) s[sn++] = ans[i] + 'a'; s[sn] = 0; if (res > f[stx][sty] || res == f[stx][sty] && strcmp(s, ress) == -1) res = f[stx][sty], memcpy(ress, s, sizeof(s)); } inline void dfs(int p, int la) { if (p > k) { work(); return; } for (int i = la; i < 26; ++i) { ena[i] = 1; ech[p] = i; dfs(p + 1, i + 1); ena[i] = 0; } } int main() { scanf("%d%d%d", &n, &m, &k); for (int i = 0; i < n; ++i) { scanf("%s", g[i]); for (int j = 0; j < m; ++j) if (g[i][j] == 'S') stx = i, sty = j; else if (g[i][j] == 'T') enx = i, eny = j; else g[i][j] -= 'a'; } res = 214748364; dfs(1, 0); if (res == 214748364) printf("-1\n"); else printf("%s\n", ress); return 0; }
#include <bits/stdc++.h> using namespace std; int k; unordered_map<char, int> used; const int N = 55; int inf = 1e9, dp[N][N], n, m, sx, sy; char s[N][N]; int tx, ty, best = inf, pos[N][N]; int dx[4] = {-1, 1, 0, 0}; int dy[4] = {0, 0, -1, 1}; string BEST = "-1"; void solve() { for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { dp[i][j] = inf; pos[i][j] = 0; } } dp[tx][ty] = 0; queue<pair<int, int> > q; q.push(make_pair(tx, ty)); while (!q.empty()) { int x = q.front().first; int y = q.front().second; q.pop(); for (int i = 0; i < 4; i++) { int nx = x + dx[i]; int ny = y + dy[i]; if (used[s[nx][ny]] && dp[nx][ny] == inf) { dp[nx][ny] = dp[x][y] + 1; q.push(make_pair(nx, ny)); } } } if (dp[sx][sy] == inf || dp[sx][sy] > best) { return; } best = dp[sx][sy]; vector<pair<int, int> > v; v.push_back(make_pair(sx, sy)); pos[sx][sy] = 1; string ans; while (1) { vector<pair<int, int> > nv; char mn = 'z' + 1; for (auto i : v) { int x = i.first; int y = i.second; for (int j = 0; j < 4; j++) { int nx = x + dx[j]; int ny = y + dy[j]; if (dp[x][y] - 1 == dp[nx][ny] && used[s[nx][ny]]) { if (mn > s[nx][ny] && !pos[nx][ny]) { nv.clear(); nv.push_back(make_pair(nx, ny)); mn = s[nx][ny]; pos[nx][ny] = 1; } else if (mn == s[nx][ny] && !pos[nx][ny]) { nv.push_back(make_pair(nx, ny)); pos[nx][ny] = 1; } } } } if (mn == 'T') { if (BEST == "-1" || BEST.size() > ans.size() || BEST > ans) { BEST = ans; } return; } ans += mn; v = nv; } } void rec(int x, int cnt) { if (x == 26) { solve(); return; } used[char(x + 'a')] = 0; rec(x + 1, cnt); if (cnt == k) return; used[char(x + 'a')] = 1; rec(x + 1, cnt + 1); } int main() { cin >> n >> m >> k; for (int i = 1; i <= n; i++) { scanf("%s", s[i] + 1); for (int j = 1; j <= m; j++) { if (s[i][j] == 'S') { sx = i; sy = j; } else if (s[i][j] == 'T') { tx = i; ty = j; } } } used['S'] = used['T'] = 1; rec(0, 0); cout << BEST; return 0; }
#include <bits/stdc++.h> using namespace std; int dx[] = {1, 0, -1, 0}; int dy[] = {0, 1, 0, -1}; int main() { long long n, m, k, sx, sy, tx, ty; cin >> n >> m >> k; vector<string> mp(n); for (long long i = 0; i < ((long long)n); i++) cin >> mp[i]; for (long long i = 0; i < ((long long)n); i++) for (long long j = 0; j < ((long long)m); j++) if (mp[i][j] == 'S') sx = i, sy = j; for (long long i = 0; i < ((long long)n); i++) for (long long j = 0; j < ((long long)m); j++) if (mp[i][j] == 'T') tx = i, ty = j; priority_queue< pair<int, pair<pair<string, int>, pair<int, int> > >, vector<pair<int, pair<pair<string, int>, pair<int, int> > > >, greater<pair<int, pair<pair<string, int>, pair<int, int> > > > > q; q.push(make_pair((abs((sx) - (tx)) + abs((sy) - (ty))), make_pair(make_pair("", 0), make_pair(sx, sy)))); set<pair<int, pair<int, int> > > s; while (((long long)q.size())) { pair<int, pair<pair<string, int>, pair<int, int> > > pp = q.top(); pair<pair<string, int>, pair<int, int> > p = pp.second; q.pop(); string str = p.first.first; int mask = p.first.second; int x = p.second.first; int y = p.second.second; if (s.find(make_pair(mask, make_pair(x, y))) != s.end()) continue; s.insert(make_pair(mask, make_pair(x, y))); for (long long i = 0; i < ((long long)4); i++) { int xx = x + dx[i]; int yy = y + dy[i]; if (xx < 0 || n <= xx || yy < 0 || m <= yy) continue; if (mp[xx][yy] == 'T') { cout << str << endl; return 0; } if ('a' <= mp[xx][yy] && mp[xx][yy] <= 'z') { int next = (1 << (mp[xx][yy] - 'a')) | mask; if (k < __builtin_popcount(next)) continue; q.push(make_pair( ((long long)str.size()) + 1 + (abs((xx) - (tx)) + abs((yy) - (ty))), make_pair(make_pair(str + string(1, mp[xx][yy]), next), make_pair(xx, yy)))); } } } cout << "-1" << endl; }
#include <bits/stdc++.h> using namespace std; bool cmp(string a, string b) { if (a.length() != b.length()) return a.length() < b.length(); return a < b; } struct node { int x, y, mask; string path; node() {} node(int x, int y, int m, string p) : x(x), y(y), mask(m), path(p) {} bool operator<(const node &p) const { return cmp(p.path, path); } }; char s[55][55]; set<int> vis[55][55]; int f[55][55]; int dx[4] = {1, -1, 0, 0}; int dy[4] = {0, 0, 1, -1}; string bfs(int x, int y, int k) { string res(55 * 55, 'a'); priority_queue<node> q; q.push(node(x, y, 0, "")); vis[x][y].insert(0); f[x][y] = 0; while (!q.empty()) { node u = q.top(); q.pop(); for (int i = 0; i < 4; i++) { int x = u.x + dx[i], y = u.y + dy[i]; if (!s[x][y] || s[x][y] == 'S') continue; if (s[x][y] == 'T') { if (cmp(u.path, res)) res = u.path; break; } int z = u.mask | (1 << (s[x][y] - 'a')); if (__builtin_popcount(z) > k) continue; if (vis[x][y].count(z)) continue; if (f[x][y] && (f[x][y] & z) == f[x][y]) continue; vis[x][y].insert(z); f[x][y] = z; q.push(node(x, y, z, u.path + s[x][y])); } } if (res.length() == 55 * 55) res = "-1"; return res; } int main() { int n, m, k; scanf("%d%d%d", &n, &m, &k); for (int i = 1; i <= n; i++) scanf("%s", s[i] + 1); for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) { if (s[i][j] == 'S') { cout << bfs(i, j, k) << endl; return 0; } } }
#include <bits/stdc++.h> using namespace std; vector<int> enumerate(int k) { vector<vector<int> > cur(k + 1); cur[0].push_back(0); cur[1].push_back(1); for (int i = 1; i < 26; i++) { vector<vector<int> > ncur = cur; for (int j = 1; j <= k && j <= i + 1; j++) { for (auto x : cur[j - 1]) { ncur[j].push_back(x ^ (1 << i)); } } cur = ncur; } vector<int> ret; for (int i = 1; i <= k; i++) { for (int x : cur[i]) { ret.push_back(x); } } return ret; } const int N = 55; const int dx[] = {1, -1, 0, 0}; const int dy[] = {0, 0, 1, -1}; string t[N]; int n, m, k, px[N][N], py[N][N], dist[N][N]; inline void bfs(int x, int y) { memset(dist, -1, sizeof(dist)); dist[x][y] = 0; queue<int> qx, qy; qx.push(x); qy.push(y); while (!qx.empty()) { x = qx.front(); qx.pop(); y = qy.front(); qy.pop(); for (int i = 0; i < 4; i++) { int nx = x + dx[i]; int ny = y + dy[i]; if (nx < 0 || nx >= n || ny < 0 || ny >= m || t[nx][ny] == '#') continue; if (dist[nx][ny] == -1) { dist[nx][ny] = dist[x][y] + 1; qx.push(nx); qy.push(ny); } } } } inline string getString(int sx, int sy, int fx, int fy) { string ret = ""; vector<pair<int, int> > pos({{sx, sy}}); int len = dist[sx][sy] - 1; for (int i = 0; i < len; i++) { vector<pair<int, int> > npos[26]; for (auto pp : pos) { int x = pp.first; int y = pp.second; for (int j = 0; j < 4; j++) { int nx = x + dx[j]; int ny = y + dy[j]; if (nx < 0 || nx >= n || ny < 0 || ny >= m || t[nx][ny] == '#') continue; if (dist[nx][ny] + 1 == dist[x][y]) { npos[t[nx][ny] - 'a'].push_back({nx, ny}); } } } for (int j = 0; j < 26; j++) { if (!npos[j].empty()) { ret += char('a' + j); pos = npos[j]; break; } } sort(pos.begin(), pos.end()); pos.resize(unique(pos.begin(), pos.end()) - pos.begin()); } return ret; } int main() { ios::sync_with_stdio(false); cin.tie(NULL); cout << setprecision(32); cin >> n >> m >> k; string s[n]; for (int i = 0; i < n; i++) { cin >> s[i]; } vector<int> masks = enumerate(k); string ans = ""; bool flg = false; for (auto mask : masks) { int sx, sy, fx, fy; for (int i = 0; i < n; i++) { t[i] = s[i]; for (int j = 0; j < m; j++) { if (t[i][j] == 'S') { sx = i; sy = j; } else if (t[i][j] == 'T') { fx = i; fy = j; } else { int ch = t[i][j] - 'a'; if (((mask >> ch) & 1) == 0) t[i][j] = '#'; } } } bfs(fx, fy); if (dist[sx][sy] == -1) continue; string cur = getString(sx, sy, fx, fy); bitset<26> bt(mask); if (flg) { if (ans.size() > cur.size()) ans = cur; else if (ans.size() == cur.size()) ans = min(ans, cur); } else { ans = cur; flg = true; } } if (flg) cout << ans; else cout << -1; return 0; }
#include <bits/stdc++.h> using namespace std; char g[55][55]; int nr, nc, k; int tr, tc, sr, sc; int mincost = -1; char chosen[5]; bool seen[500]; char ans[3000]; int dr[] = {-1, 1, 0, 0}; int dc[] = {0, 0, 1, -1}; void check() { int d[55][55]; memset((d), (-1), sizeof(d)); d[tr][tc] = 0; queue<int> q; q.push(tr); q.push(tc); while (!q.empty()) { int r = q.front(); q.pop(); int c = q.front(); q.pop(); int dist = d[r][c] + 1; for (int i = 0, _e(4); i < _e; i++) { int rr = r + dr[i], cc = c + dc[i]; if (rr < 0 || cc < 0 || rr >= nr || cc >= nc || (g[rr][cc] != 'S' && !seen[g[rr][cc] - 'a'])) continue; if (d[rr][cc] == -1 || d[rr][cc] > dist) { d[rr][cc] = dist; q.push(rr); q.push(cc); } } } if (d[sr][sc] != -1 && (mincost == -1 || mincost >= d[sr][sc])) { if (mincost == -1 || mincost > d[sr][sc]) { mincost = d[sr][sc]; queue<int> q; int r = sr, c = sc; q.push(r); q.push(c); for (int j = 0, _e(mincost - 1); j < _e; j++) { int tot = q.size() / 2; char minC = 'z'; queue<int> p; int taken[55][55] = {}, take = 1; for (int l = 0, _e(tot); l < _e; l++) { r = q.front(); q.pop(); c = q.front(); q.pop(); int look = mincost - j - 1; for (int i = 0, _e(4); i < _e; i++) { int rr = r + dr[i], cc = c + dc[i]; if (rr < 0 || cc < 0 || rr >= nr || cc >= nc || (!seen[g[rr][cc] - 'a'])) continue; if (d[rr][cc] == look) { if (g[rr][cc] < minC) { while (p.size()) p.pop(); ++take, minC = g[rr][cc], p.push(rr), p.push(cc), taken[rr][cc] = take; } else if (g[rr][cc] == minC && taken[rr][cc] != take) { p.push(rr), p.push(cc), taken[rr][cc] = take; } } } } ans[j] = minC; q = p; } } else { queue<int> q; int r = sr, c = sc; q.push(r); q.push(c); char dans[3000]; for (int j = 0, _e(mincost - 1); j < _e; j++) { int tot = q.size() / 2; char minC = 'z'; queue<int> p; int taken[55][55] = {}, take = 0; for (int l = 0, _e(tot); l < _e; l++) { r = q.front(); q.pop(); c = q.front(); q.pop(); int look = mincost - j - 1; for (int i = 0, _e(4); i < _e; i++) { int rr = r + dr[i], cc = c + dc[i]; if (rr < 0 || cc < 0 || rr >= nr || cc >= nc || (!seen[g[rr][cc] - 'a'])) continue; if (d[rr][cc] == look) { if (g[rr][cc] < minC) { while (p.size()) p.pop(); ++take, minC = g[rr][cc], p.push(rr), p.push(cc), taken[rr][cc] = take; } else if (g[rr][cc] == minC && taken[rr][cc] != take) { p.push(rr), p.push(cc), taken[rr][cc] = take; } } } } dans[j] = minC; q = p; } bool better = 0; for (int i = 0, _e(mincost - 1); i < _e; i++) if (ans[i] < dans[i]) break; else if (ans[i] > dans[i]) better = 1; if (better) { for (int i = 0, _e(mincost - 1); i < _e; i++) ans[i] = dans[i]; } } } } void dfs(int p, int last) { if (p) check(); if (p == k) return; for (int i(last), _e(25); i <= _e; i++) if (!seen[i]) { seen[i] = 1; chosen[p] = i + 'a'; dfs(p + 1, i + 1); seen[i] = 0; } } int main() { cin >> nr >> nc >> k; for (int i = 0, _e(nr); i < _e; i++) cin >> g[i]; for (int i = 0, _e(nr); i < _e; i++) for (int j = 0, _e(nc); j < _e; j++) if (g[i][j] == 'T') tr = i, tc = j; else if (g[i][j] == 'S') sr = i, sc = j; dfs(0, 0); if (mincost == -1) { cout << -1 << endl; return 0; } for (int i = 0, _e(mincost - 1); i < _e; i++) cout << ans[i]; cout << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int M = 50 + 10; char board[M][M]; char graph[M][M]; struct NODE { int parent_row; int parent_col; int dis; int visited; string par; } node[M][M]; int cnt = 0; int pattern[26 * 25 * 23 + 10][4]; void nchoosek(int num, int *a, int tar, int len, int isize, int spe) { if (isize == tar) { int j = 0; for (int i = 0; i < len; i++) { if (a[i] == 1) { pattern[cnt][j] = i; j++; } } cnt++; return; } else { for (int i = num; i < len; i++) { if (i != spe) { a[i] = 1; nchoosek(i + 1, a, tar, len, isize + 1, spe); a[i] = 0; } } return; } } string ans; int LEN = 1E+9; int dir[8] = {0, 1, 0, -1, -1, 0, 1, 0}; int n, m; void BFS(int sr, int sc, int er, int ec) { queue<pair<int, int> > Q; Q.push(make_pair(sr, sc)); node[sr][sc].visited = 1; node[sr][sc].dis = 0; while (!Q.empty()) { int row = Q.front().first; int col = Q.front().second; Q.pop(); for (int i = 0; i < 8; i = i + 2) { int nrow = row + dir[i]; int ncol = col + dir[i + 1]; if (nrow >= 0 && nrow < n && ncol >= 0 && ncol < m && (graph[nrow][ncol] == 'O' || graph[nrow][ncol] == 'T')) { if (node[nrow][ncol].visited == 1) { if (node[nrow][ncol].dis == node[row][col].dis + 1) { int prow = node[nrow][ncol].parent_row; int pcol = node[nrow][ncol].parent_col; if (node[row][col].par < node[prow][pcol].par) { node[nrow][ncol].parent_row = row; node[nrow][ncol].parent_col = col; node[nrow][ncol].par = node[row][col].par + board[nrow][ncol]; } } } else { node[nrow][ncol].parent_row = row; node[nrow][ncol].parent_col = col; node[nrow][ncol].dis = node[row][col].dis + 1; node[nrow][ncol].visited = 1; node[nrow][ncol].par = node[row][col].par + board[nrow][ncol]; if (nrow == er && ncol == ec) { ; } else { Q.push(make_pair(nrow, ncol)); } } } } } if (node[er][ec].visited == 1) { int row = er; int col = ec; vector<char> tmp; while (row != sr || col != sc) { tmp.push_back(board[row][col]); int irow = node[row][col].parent_row; int icol = node[row][col].parent_col; row = irow; col = icol; } tmp.push_back(board[sr][sc]); if (tmp.size() < LEN) { ans = ""; for (int i = tmp.size() - 1; i >= 0; i--) { ans = ans + tmp[i]; } LEN = tmp.size(); } else { if (tmp.size() == LEN) { string ss = ""; for (int i = tmp.size() - 1; i >= 0; i--) { ss += tmp[i]; } if (ss < ans) { ans = ss; } } } } return; } int main() { int k; cin >> n >> m >> k; set<char> letter; int sr, sc; int er, ec; for (int i = 0; i < n; i++) { string s; cin >> s; for (int j = 0; j < m; j++) { board[i][j] = s[j]; if (s[j] == 'S') { sr = i; sc = j; } if (s[j] == 'T') { er = i; ec = j; } if (s[j] != 'S' && s[j] != 'T') { letter.insert(s[j]); } } } vector<char> grid; for (set<char>::iterator it = letter.begin(); it != letter.end(); it++) { grid.push_back(*it); } sort(grid.begin(), grid.end()); if (grid.size() < k) { k = grid.size(); } for (int kk = 0; kk < 8; kk += 2) { int isr = sr + dir[kk]; int isc = sc + dir[kk + 1]; if (isr >= 0 && isr < n && isc >= 0 && isc < m) { for (int ksize = 1; ksize <= k; ksize++) { cnt = 0; int a[26]; for (int j = 0; j < grid.size(); j++) { a[j] = 0; } char cc = board[isr][isc]; int inum = -1; for (int ii = 0; ii < grid.size(); ii++) { if (grid[ii] == cc) { inum = ii; break; } } a[inum] = 1; nchoosek(0, a, ksize, grid.size(), 1, inum); for (int i = 0; i < cnt; i = i + 1) { for (int row = 0; row < n; row++) { for (int col = 0; col < m; col++) { if (board[row][col] == 'S') { graph[row][col] = 'S'; } if (board[row][col] == 'T') { graph[row][col] = 'T'; } if (board[row][col] != 'S' && board[row][col] != 'T') { graph[row][col] = 'X'; for (int j = 0; j < ksize; j++) { if (board[row][col] == grid[pattern[i][j]]) { graph[row][col] = 'O'; } } } node[row][col].visited = 0; } } BFS(isr, isc, er, ec); } } } } if (LEN == 1E+9) { if (n * m > 2) cout << "-1" << endl; } else { for (int i = 0; i < ans.size() - 1; i++) { cout << ans[i]; } cout << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; int dx[4] = {-1, 0, 1, 0}; int dy[4] = {0, 1, 0, -1}; pair<int, int> st, en; int m, n, k; char a[55][55]; bool b[55][55]; int d[55][55]; string Z[55][55]; bool inq[55][55]; int solve1() { queue<pair<int, int> > q; q.push(st); memset(d, 0x1f, sizeof(d)); d[st.first][st.second] = 0; while (!q.empty()) { int u = q.front().first; int v = q.front().second; q.pop(); for (int h = 0; h < (4); ++h) { int x = u + dx[h]; int y = v + dy[h]; if (0 <= x && x < m && 0 <= y && y < n && b[x][y]) { if (d[x][y] > d[u][v] + 1) { d[x][y] = d[u][v] + 1; q.push(make_pair(x, y)); } } } } return d[en.first][en.second]; } string solve2() { queue<pair<int, int> > q; memset(inq, 0, sizeof(inq)); q.push(st); inq[st.first][st.second] = true; Z[st.first][st.second] = ""; while (!q.empty()) { int u = q.front().first; int v = q.front().second; q.pop(); for (int h = 0; h < (4); ++h) { int x = u + dx[h]; int y = v + dy[h]; if (0 <= x && x < m && 0 <= y && y < n && b[x][y]) { if (d[x][y] == d[u][v] + 1) { if (!inq[x][y]) { q.push(make_pair(x, y)); inq[x][y] = true; Z[x][y] = Z[u][v] + a[x][y]; } else if (Z[x][y] > Z[u][v] + a[x][y]) Z[x][y] = Z[u][v] + a[x][y]; } } } } return Z[en.first][en.second]; } int main() { scanf("%d%d%d", &m, &n, &k); gets(a[0]); for (int i = 0; i < (m); ++i) gets(a[i]); for (int i = 0; i < (m); ++i) for (int j = 0; j < (n); ++j) if (a[i][j] == 'S') st = make_pair(i, j); else if (a[i][j] == 'T') en = make_pair(i, j); int res = 50 * 50 * 50; for (int c1 = 0; c1 < (26); ++c1) for (int c2 = 0; c2 < (c1 + 1); ++c2) for (int c3 = 0; c3 < (c2 + 1); ++c3) for (int c4 = 0; c4 < (c3 + 1); ++c4) { set<int> second; second.insert(c1); second.insert(c2); second.insert(c3); second.insert(c4); if (second.size() == k) { memset(b, 0, sizeof(b)); for (int i = 0; i < (m); ++i) for (int j = 0; j < (n); ++j) if (a[i][j] == 'S' || a[i][j] == 'T' || second.count(a[i][j] - 'a')) b[i][j] = true; int len = solve1(); res = min(res, len); } } if (res == 50 * 50 * 50) cout << -1 << endl; else { string beststr = ""; for (int c1 = 0; c1 < (26); ++c1) for (int c2 = 0; c2 < (c1 + 1); ++c2) for (int c3 = 0; c3 < (c2 + 1); ++c3) for (int c4 = 0; c4 < (c3 + 1); ++c4) { set<int> second; second.insert(c1); second.insert(c2); second.insert(c3); second.insert(c4); if (second.size() == k) { memset(b, 0, sizeof(b)); for (int i = 0; i < (m); ++i) for (int j = 0; j < (n); ++j) if (a[i][j] == 'S' || a[i][j] == 'T' || second.count(a[i][j] - 'a')) b[i][j] = true; int len = solve1(); if (len == res) { string path = solve2(); if (beststr == "" || beststr > path) beststr = path; } } } beststr = beststr.substr(0, beststr.length() - 1); cout << beststr << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; namespace IO { const int sz = 1 << 15; char inbuf[sz], outbuf[sz]; char *pinbuf = inbuf + sz; char *poutbuf = outbuf; inline char _getchar() { if (pinbuf == inbuf + sz) fread(inbuf, 1, sz, stdin), pinbuf = inbuf; return *(pinbuf++); } inline void _putchar(char x) { if (poutbuf == outbuf + sz) fwrite(outbuf, 1, sz, stdout), poutbuf = outbuf; *(poutbuf++) = x; } inline void flush() { if (poutbuf != outbuf) fwrite(outbuf, 1, poutbuf - outbuf, stdout), poutbuf = outbuf; } } // namespace IO inline int read() { int x = 0, p = 1; char c = getchar(); while (c < '0' || c > '9') { if (c == '-') p = -1; c = getchar(); } while (c >= '0' && c <= '9') x = x * 10 + c - 48, c = getchar(); return x * p; } namespace Mymath { long long qp(long long x, long long p, long long mod) { long long ans = 1; while (p) { if (p & 1) ans = ans * x % mod; x = x * x % mod; p >>= 1; } return ans; } long long inv(long long x, long long mod) { return qp(x, mod - 2, mod); } long long C(long long N, long long K, long long fact[], long long mod) { return fact[N] * inv(fact[K], mod) % mod * inv(fact[N - K], mod) % mod; } template <typename Tp> Tp gcd(Tp A, Tp B) { if (B == 0) return A; return gcd(B, A % B); } template <typename Tp> Tp lcm(Tp A, Tp B) { return A * B / gcd(A, B); } }; // namespace Mymath const int Maxn = 55; const int dx[] = {0, 0, 1, -1}; const int dy[] = {1, -1, 0, 0}; char c[Maxn][Maxn]; int n, m, k, sx, sy, ex, ey; vector<vector<int> > V; vector<int> now; void dfs(int lvl) { if (lvl == k) { V.push_back(now); return; } int lst = (now.empty()) ? 0 : now.back() + 1; for (int i = lst; i < 26; i++) { now.push_back(i); dfs(lvl + 1); now.pop_back(); } } int ds[Maxn][Maxn], dt[Maxn][Maxn]; bool G[27]; int qx[Maxn * Maxn], qy[Maxn * Maxn], eq, kq; void bfs(int x, int y, int dist[Maxn][Maxn]) { for (int i = 0; i < Maxn; i++) { for (int j = 0; j < Maxn; j++) { dist[i][j] = -1; } } dist[x][y] = 0; kq = eq = 0; qx[eq] = x; qy[eq++] = y; while (kq < eq) { int X = qx[kq], Y = qy[kq++]; for (int i = 0; i < 4; i++) { int nx = X + dx[i], ny = Y + dy[i]; if (nx >= 0 && ny >= 0 && nx < n && ny < m && (c[nx][ny] == 'S' || c[nx][ny] == 'T' || G[c[nx][ny] - 'a'])) { if (dist[nx][ny] == -1) { dist[nx][ny] = dist[X][Y] + 1; qx[eq] = nx; qy[eq++] = ny; } } } } } int anslen = 1e9; string ans; bool vis[Maxn][Maxn]; int main() { scanf("%d%d%d", &n, &m, &k); for (int i = 0; i < n; i++) { scanf("%s", c[i]); for (int j = 0; j < m; j++) { if (c[i][j] == 'S') { sx = i; sy = j; } if (c[i][j] == 'T') { ex = i; ey = j; } } } dfs(0); for (int i = 0; i < V.size(); i++) { memset(G, 0, sizeof(G)); memset(vis, 0, sizeof(vis)); for (int j = 0; j < V[i].size(); j++) { G[V[i][j]] = 1; } bfs(sx, sy, ds); bfs(ex, ey, dt); if (ds[ex][ey] == -1) continue; string cur; int dst = ds[ex][ey]; vector<pair<int, int> > Now, Nxt; char cc = 'z' + 1; Now.push_back(make_pair(sx, sy)); for (int j = 1; j < dst; j++) { cc = 'z' + 1; for (int t = 0; t < Now.size(); t++) { int x = Now[t].first, y = Now[t].second; for (int d = 0; d < 4; d++) { int nx = x + dx[d], ny = y + dy[d]; if (nx >= 0 && ny >= 0 && nx < n && ny < m && !vis[nx][ny] && j + dt[nx][ny] == dst) { vis[nx][ny] = 1; char now = c[nx][ny]; if (now < cc) { Nxt.clear(); cc = now; } if (now == cc) { Nxt.push_back(make_pair(nx, ny)); } } } } cur += cc; Now = Nxt; Nxt.clear(); } if (anslen > dst) { anslen = dst; ans = cur; } else if (anslen == dst) { if (cur < ans) ans = cur; } } if (anslen == 1e9) { printf("-1\n"); return 0; } printf("%s\n", ans.c_str()); return 0; }
#include <bits/stdc++.h> using namespace std; string mat[50]; bool allow[26]; bool isAllow(char c) { return c == 'T' || c == 'S' || allow[c - 'a']; } int di[] = {0, 0, 1, -1}; int dj[] = {1, -1, 0, 0}; int dist[50][50]; pair<int, int> pa[50][50]; int n, m; bool in(int a, int b) { return 0 <= a && a < n && 0 <= b && b < m; } void bfs(int x, int y) { pair<int, int> orig = make_pair(x, y); queue<pair<int, int> > cola; memset(dist, -1, sizeof(dist)); int vis[n][m]; memset(vis, 0, sizeof(vis)); cola.push(orig); vis[x][y] = true; dist[x][y] = 0; while (!cola.empty()) { pair<int, int> cu = cola.front(); cola.pop(); int xx = cu.first, yy = cu.second; for (int k = 0; k < 4; k++) { int nx = xx + di[k], ny = yy + dj[k]; if (in(nx, ny) && isAllow(mat[nx][ny])) { if (!vis[nx][ny]) { dist[nx][ny] = dist[xx][yy] + 1; pa[nx][ny] = cu; vis[nx][ny] = true; cola.push(make_pair(nx, ny)); } else if (dist[nx][ny] == dist[xx][yy] + 1) { pair<int, int> p1 = cu, p2 = pa[nx][ny]; while (p1 != orig && mat[p1.first][p1.second] == mat[p2.first][p2.second]) { p1 = pa[p1.first][p1.second]; p2 = pa[p2.first][p2.second]; } if (p1 != orig && mat[p1.first][p1.second] < mat[p2.first][p2.second]) { pa[nx][ny] = cu; } } } } } } int main() { int kk; cin >> n >> m >> kk; int xS, yS, xT, yT; for (int i = 0; i < n; i++) { cin >> mat[i]; } for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { if (mat[i][j] == 'S') { xS = i; yS = j; } if (mat[i][j] == 'T') { xT = i; yT = j; } } pair<int, int> final = make_pair(xT, yT); string best; int largo = 1000000000; memset(allow, 0, sizeof(allow)); bool first = true; for (int i = 0; i < 26; i++) for (int j = i; j < 26; j++) for (int k = j; k < 26; k++) for (int h = k; h < 26; h++) { if (kk < 4) h = i; if (kk < 3) k = i; if (kk < 2) j = i; allow[i] = allow[j] = allow[k] = allow[h] = true; bfs(xT, yT); if (dist[xS][yS] != -1) { int cu = dist[xS][yS]; if (cu <= largo) { string curS = ""; pair<int, int> po = pa[xS][yS]; while (po != final) { curS += mat[po.first][po.second]; po = pa[po.first][po.second]; } if (cu < largo) { largo = cu; best = curS; } else if (cu == largo && best > curS) { best = curS; } } } allow[i] = allow[j] = allow[k] = allow[h] = false; if (kk < 4) h = 26; if (kk < 3) k = 26; if (kk < 2) j = 26; } if (largo >= 1000000000) cout << "-1" << endl; else { cout << best << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; const int dx[] = {0, 0, 1, -1}; const int dy[] = {1, -1, 0, 0}; int N, M, K; int F[60][60], Q[3000][2]; int SX, SY, TX, TY; string P[60][60]; pair<char, int> A[4]; string Ret; char Map[60][60]; bool G[60][60], Choose[30]; inline void BFS() { memset(G, false, sizeof(G)); for (int i = 1; i <= N; i++) { for (int j = 1; j <= M; j++) if (Choose[Map[i][j] - 'a']) { G[i][j] = true; } } G[SX][SY] = true; G[TX][TY] = true; memset(F, -1, sizeof(F)); F[SX][SY] = 0; int Head = 0, Tail = 1; Q[1][0] = SX; Q[1][1] = SY; while (Head++ < Tail) { int x = Q[Head][0]; int y = Q[Head][1]; if (x == TX && y == TY) { break; } if (x != SX || y != SY) { P[x][y] += Map[x][y]; } for (int i = 0; i < 4; i++) { int u = x + dx[i]; int v = y + dy[i]; if (!G[u][v]) { continue; } if (F[u][v] == -1) { F[u][v] = F[x][y] + 1; P[u][v] = P[x][y]; Tail++; Q[Tail][0] = u; Q[Tail][1] = v; } else if (F[x][y] + 1 == F[u][v] && P[x][y] < P[u][v]) { P[u][v] = P[x][y]; } } } if (F[TX][TY] == -1) { return; } if (Ret != "-1" && F[TX][TY] > Ret.size() + 1) { return; } string Ans = P[TX][TY]; if (Ret == "-1" || Ans.size() < Ret.size() || Ans < Ret) { Ret = Ans; } } inline void Search(int k, int total) { if (total > K) { return; } if (k == 26) { if (total == K) { BFS(); } } else { Choose[k] = true; Search(k + 1, total + 1); Choose[k] = false; Search(k + 1, total); } } int main(int argc, char *argv[]) { scanf("%d%d%d", &N, &M, &K); for (int i = 1; i <= N; i++) { scanf("%s", Map[i] + 1); for (int j = 1; j <= M; j++) { if (Map[i][j] == 'S') { SX = i; SY = j; Map[i][j] = 'a'; } if (Map[i][j] == 'T') { TX = i; TY = j; Map[i][j] = 'a'; } } } Ret = "-1"; Search(0, 0); cout << Ret << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int dx[4] = {1, 0, -1, 0}; const int dy[5] = {0, 1, 0, -1}; string res = ""; int que[55 * 55][2], _que[55 * 55][2]; int dist[55][55]; bool p[55][55]; char g[55][55]; int n, m, limit; int sx, sy, tx, ty; bool flag[100]; int main() { scanf("%d%d%d", &n, &m, &limit); for (int i = 0; i < n; i++) scanf("%s", g[i]); for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) if (g[i][j] == 'S') sx = i, sy = j; else if (g[i][j] == 'T') tx = i, ty = j; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) if (g[i][j] >= 'a' && g[i][j] <= 'z') flag[g[i][j] - 'a'] = 1; flag[26] = 1; if (abs(sx - tx) + abs(sy - ty) == 1) return 0; for (int i = 0; i < 26; i++) if (flag[i]) for (int j = i + 1; j < 27; j++) if (flag[j]) { if (j < 26 && limit == 1) continue; for (int k = j; k < 27; k++) if (flag[k]) { if (k < 26 && limit == 2) continue; if (k == j && k < 26) continue; for (int l = k; l < 27; l++) if (flag[l]) { if (l < 26 && limit == 3) continue; if (l == k && l < 26) continue; int XXX = (1 << i) + (1 << j) + (1 << k) + (1 << l); for (int a = 0; a < n; a++) for (int b = 0; b < m; b++) dist[a][b] = -1, p[a][b] = 0; dist[tx][ty] = 0; que[0][0] = tx; que[0][1] = ty; int r = 0; for (int l = 0; dist[sx][sy] == -1 && l <= r; l++) { int u = que[l][0], v = que[l][1]; for (int w = 0; w < 4; w++) if (u + dx[w] >= 0 && u + dx[w] < n && v + dy[w] >= 0 && v + dy[w] < m && dist[u + dx[w]][v + dy[w]] == -1) { if (sx == u + dx[w] && sy == v + dy[w]) { dist[sx][sy] = dist[u][v] + 1; continue; } int uu = u + dx[w], vv = v + dy[w]; if (XXX & (1 << (g[uu][vv] - 'a'))) { dist[uu][vv] = dist[u][v] + 1; que[++r][0] = uu; que[r][1] = vv; } } } if (dist[sx][sy] != -1) { string tmp = ""; int r = 0; que[0][0] = sx; que[0][1] = sy; while (tmp.size() != dist[sx][sy] - 1) { char ww = 'z' + 1; for (int l = 0; l <= r; l++) { int u = que[l][0], v = que[l][1]; for (int w = 0; w < 4; w++) { int uu = u + dx[w], vv = v + dy[w]; if (uu >= 0 && uu < n && vv >= 0 && vv < m && dist[uu][vv] != -1 && dist[uu][vv] + tmp.size() == dist[sx][sy] - 1) ww = min(ww, g[uu][vv]); } } int _r = -1; for (int l = 0; l <= r; l++) { int u = que[l][0], v = que[l][1]; for (int w = 0; w < 4; w++) { int uu = u + dx[w], vv = v + dy[w]; if (uu >= 0 && uu < n && vv >= 0 && vv < m && !p[uu][vv] && dist[uu][vv] != -1 && dist[uu][vv] + tmp.size() == dist[sx][sy] - 1 && g[uu][vv] == ww) { p[uu][vv] = 1; _que[++_r][0] = uu; _que[_r][1] = vv; } } } r = _r; for (int l = 0; l <= r; l++) que[l][0] = _que[l][0], que[l][1] = _que[l][1]; tmp += ww; } if (!res.size() || (res.size() > tmp.size()) || (res.size() == tmp.size() && res > tmp)) res = tmp; } } } } if (!res.size()) printf("-1\n"); else cout << res << endl; }
#include <bits/stdc++.h> using namespace std; int n, m, k; int sx, sy, gy, gx; vector<string> mat; int dx[] = {0, 0, -1, 1}; int dy[] = {1, -1, 0, 0}; long long dis(int y1, int y2, int x2, int x1) { return abs(y2 - y1) + abs(x2 - x1); } int main() { cin >> n >> m >> k; for (int i = 0; i < n; i++) { string str; cin >> str; mat.push_back(str); for (int j = 0; j < str.size(); j++) { if (str[j] == 'S') { sx = j; sy = i; } if (str[j] == 'T') { gx = j; gy = i; } } } priority_queue< pair<long long, pair<pair<string, long long>, long long> >, vector<pair<long long, pair<pair<string, long long>, long long> > >, greater<pair<long long, pair<pair<string, long long>, long long> > > > pq; pq.push( make_pair(dis(gy, sy, gx, sx), make_pair(make_pair("", 0), sy * m + sx))); set<pair<long long, long long> > ss; while (!pq.empty()) { int nt = pq.top().first; string nstr = pq.top().second.first.first; int nmask = pq.top().second.first.second; int nx = pq.top().second.second % m; int ny = pq.top().second.second / m; int nn = pq.top().second.second; pq.pop(); if (ss.count(make_pair(nn, nmask))) continue; ss.insert(make_pair(nn, nmask)); for (int i = 0; i < 4; i++) { int ax = nx + dx[i]; int ay = ny + dy[i]; if (ax < 0 || ax >= m || ay < 0 || ay >= n) continue; if (ay == gy && ax == gx) { cout << nstr << endl; return 0; } string astr = nstr + mat[ay][ax]; int nnmask = nmask | (1 << (mat[ay][ax] - 'a')); if (__builtin_popcount(nnmask) <= k) { pq.push(make_pair(dis(ay, gy, ax, gx) + astr.size(), make_pair(make_pair(astr, nnmask), ay * m + ax))); } } } cout << -1 << endl; return 0; }
#include <bits/stdc++.h> using namespace std; class MPI { public: vector<long long int> MPI_VALUE; bool MPI_SIGN; MPI(const string &mpi_s) { MPI_SIGN = false; if (((long long int)(mpi_s).size())) { if (mpi_s[0] == '-') MPI_SIGN = true; for (long long int i = ((long long int)(mpi_s).size()) - 1; ((mpi_s[0] == '-') ? 1 : 0) <= i; i -= 6) { long long int mpi_sum = 0; long long int mpi_base = 1; for (long long int j = 0; j < ((long long int)(6)); j++) if (((mpi_s[0] == '-') ? 1 : 0) <= i - j) { mpi_sum += (mpi_s[i - j] - '0') * mpi_base; mpi_base *= 10; } MPI_VALUE.push_back(mpi_sum); } } mpi_reform(*this); } MPI(const vector<long long int> &mpi_vec) { MPI_SIGN = false; MPI_VALUE = mpi_vec; mpi_reform(*this); } MPI(int mpi_val) { MPI_SIGN = false; if (mpi_val < 0) { mpi_val = -mpi_val; MPI_SIGN = true; } while (mpi_val) { MPI_VALUE.push_back(mpi_val % 1000000); mpi_val /= 1000000; } mpi_reform(*this); } MPI(long long int mpi_val) { MPI_SIGN = false; if (mpi_val < 0) { mpi_val = -mpi_val; MPI_SIGN = true; } while (mpi_val) { MPI_VALUE.push_back(mpi_val % 1000000); mpi_val /= 1000000; } mpi_reform(*this); } MPI(bool mpi_need0, bool mpi_need1) { MPI_SIGN = false; } MPI() { MPI_SIGN = false; MPI_VALUE.push_back(0); } string to_string() const { string mpi_res = ""; long long int mpi_p10[6 + 1]; for (long long int i = 0; i < ((long long int)(6 + 1)); i++) mpi_p10[i] = (i) ? (mpi_p10[i - 1] * 10) : 1; for (long long int i = ((long long int)(MPI_VALUE).size()) - 1; 0 <= i; i--) for (long long int j = 0; j < ((long long int)(6)); j++) { long long int mpi_tmp = (MPI_VALUE[i] % mpi_p10[6 - j]) / mpi_p10[6 - j - 1]; if (((long long int)(mpi_res).size()) || mpi_tmp) mpi_res += string(1, '0' + mpi_tmp); } if (((long long int)(mpi_res).size()) == 0) mpi_res += "0"; else if (MPI_SIGN) mpi_res = "-" + mpi_res; return mpi_res; } long long int to_long() const { long long int mpi_res = 0; long long int mpi_base = 1; for (long long int i = 0; i < ((long long int)(((long long int)(MPI_VALUE).size()))); i++) { mpi_res += MPI_VALUE[i] * mpi_base; mpi_base *= 1000000; } if (MPI_SIGN) mpi_res = -mpi_res; return mpi_res; } long long int size() const { long long int mpi_res = (((long long int)(MPI_VALUE).size()) - 1) * 6; long long int mpi_tmp = MPI_VALUE.back(); while (mpi_tmp) { mpi_res++; mpi_tmp /= 10; } return mpi_res; } static MPI mpi_abs_add(const MPI &mpi0, const MPI &mpi1) { MPI mpi_res(false, false); long long int carry = 0; for (long long int i = 0; i < ((long long int)(max(((long long int)(mpi0.MPI_VALUE).size()), ((long long int)(mpi1.MPI_VALUE).size())))); i++) { long long int mpi_t0 = (i < ((long long int)(mpi0.MPI_VALUE).size())) ? (mpi0.MPI_VALUE[i]) : 0; long long int mpi_t1 = (i < ((long long int)(mpi1.MPI_VALUE).size())) ? (mpi1.MPI_VALUE[i]) : 0; long long int mpi_t = mpi_t0 + mpi_t1 + carry; mpi_res.MPI_VALUE.push_back(mpi_t % 1000000); carry = mpi_t / 1000000; } if (carry) mpi_res.MPI_VALUE.push_back(carry); mpi_reform(mpi_res); return mpi_res; } static MPI mpi_abs_sub_sub(const MPI &mpi0, const MPI &mpi1) { MPI mpi_res(false, false); mpi_res.MPI_VALUE = mpi0.MPI_VALUE; long long int carry = 0; for (long long int i = 0; i < ((long long int)(mpi1.MPI_VALUE).size()) || carry; i++) { mpi_res.MPI_VALUE[i] -= carry; carry = 0; if (i < ((long long int)(mpi1.MPI_VALUE).size())) mpi_res.MPI_VALUE[i] = mpi_res.MPI_VALUE[i] - mpi1.MPI_VALUE[i]; if (mpi_res.MPI_VALUE[i] < 0) { carry++; mpi_res.MPI_VALUE[i] += 1000000; } } mpi_reform(mpi_res); return mpi_res; } static MPI mpi_abs_sub(const MPI &mpi0, const MPI &mpi1) { if (!mpi_abs_gt(mpi0, mpi1)) return mpi_abs_sub_sub(mpi0, mpi1); MPI mpi_res = mpi_abs_sub_sub(mpi1, mpi0); mpi_res.MPI_SIGN = !mpi_res.MPI_SIGN; return mpi_res; } static MPI mpi_abs_mul(const MPI &mpi0, const MPI &mpi1) { MPI mpi_res(false, false); mpi_res.MPI_VALUE = vector<long long int>(((long long int)(mpi0.MPI_VALUE).size()) + ((long long int)(mpi1.MPI_VALUE).size()), 0); for (long long int i = 0; i < ((long long int)(((long long int)(mpi0.MPI_VALUE).size()))); i++) if (mpi0.MPI_VALUE[i]) { for (long long int j = 0; j < ((long long int)(((long long int)(mpi1.MPI_VALUE).size()))); j++) { mpi_res.MPI_VALUE[i + j] += mpi0.MPI_VALUE[i] * mpi1.MPI_VALUE[j]; } } mpi_add_mul_reform(mpi_res); return mpi_res; } MPI operator+(const MPI &mpi_var) const { bool b0 = MPI_SIGN, b1 = mpi_var.MPI_SIGN; if (!b0 && !b1) return mpi_abs_add(*this, mpi_var); if (!b0 && b1) return mpi_abs_sub(*this, mpi_var); if (b0 && !b1) return mpi_abs_sub(mpi_var, *this); MPI mpi_res = mpi_abs_add(*this, mpi_var); mpi_res.MPI_SIGN = !mpi_res.MPI_SIGN; return mpi_res; } MPI operator-(const MPI &mpi_var) const { bool b0 = MPI_SIGN, b1 = mpi_var.MPI_SIGN; if (!b0 && !b1) return mpi_abs_sub(*this, mpi_var); if (!b0 && b1) return mpi_abs_add(*this, mpi_var); if (b0 && b1) return mpi_abs_sub(mpi_var, *this); MPI mpi_res = mpi_abs_add(*this, mpi_var); mpi_res.MPI_SIGN = !mpi_res.MPI_SIGN; return mpi_res; } MPI operator*(const MPI &mpi_var) const { bool b0 = MPI_SIGN, b1 = mpi_var.MPI_SIGN; if (b0 && b1) return mpi_abs_mul(*this, mpi_var); if (!b0 && !b1) return mpi_abs_mul(*this, mpi_var); MPI mpi_res = mpi_abs_mul(*this, mpi_var); mpi_res.MPI_SIGN = !mpi_res.MPI_SIGN; return mpi_res; } friend std::ostream &operator<<(std::ostream &os, const MPI &mpi_var) { os << mpi_var.to_string(); return os; } friend std::istream &operator>>(std::istream &is, MPI &mpi_var) { string mpi_str; is >> mpi_str; mpi_var = MPI(mpi_str); return is; } static void mpi_subst(MPI &mpi_from, const MPI &mpi_base, long long int mpi_cons, long long int mpi_shift) { long long int carry = 0; for (long long int i = 0; i + mpi_shift < ((long long int)(mpi_from.MPI_VALUE).size()); i++) { mpi_from.MPI_VALUE[mpi_shift + i] -= carry; carry = 0; if (i < ((long long int)(mpi_base.MPI_VALUE).size())) { carry = (mpi_base.MPI_VALUE[i] * mpi_cons) / 1000000; mpi_from.MPI_VALUE[mpi_shift + i] -= (mpi_base.MPI_VALUE[i] * mpi_cons) % 1000000; } while (mpi_from.MPI_VALUE[mpi_shift + i] < 0) { carry++; mpi_from.MPI_VALUE[mpi_shift + i] += 1000000; } } } static bool mpi_can_sub(const MPI &mpi_from, const MPI &mpi_base, long long int mpi_cons, long long int mpi_shift) { long long int carry = 0; for (long long int i = 0; i + mpi_shift < ((long long int)(mpi_from.MPI_VALUE).size()); i++) { long long int mpi_tmp = carry; if (i < ((long long int)(mpi_base.MPI_VALUE).size())) mpi_tmp += mpi_base.MPI_VALUE[i] * mpi_cons; long long int mpi_dif = (mpi_tmp - mpi_from.MPI_VALUE[i + mpi_shift]); if (mpi_dif < 0) carry = 0; else carry = ((mpi_dif % 1000000) ? 1 : 0) + mpi_dif / 1000000; } return carry == 0; } static MPI mpi_abs_div_small(const MPI &mpi_den, const MPI &mpi_num, bool is_div) { MPI mpi_ans(false, false); MPI mpi_rem(mpi_den.MPI_VALUE); mpi_ans.MPI_VALUE = vector<long long int>(((long long int)(mpi_rem.MPI_VALUE).size()), 0); long long int mpi_cons = abs(mpi_num.to_long()), carry = 0; for (long long int i = ((long long int)(mpi_rem.MPI_VALUE).size()) - 1; 0 <= i; i--) { mpi_rem.MPI_VALUE[i] += carry * 1000000; carry = mpi_rem.MPI_VALUE[i] % mpi_cons; mpi_ans.MPI_VALUE[i] = mpi_rem.MPI_VALUE[i] / mpi_cons; } if (!is_div) return MPI(carry); mpi_reform(mpi_ans); return mpi_ans; } static MPI mpi_abs_div(const MPI &mpi_den, const MPI &mpi_num, bool is_div) { if (mpi_abs_gt(mpi_num, 1000000)) return mpi_abs_div_small(mpi_den, mpi_num, is_div); MPI mpi_ans(0); MPI mpi_rem(mpi_den.MPI_VALUE); mpi_ans.MPI_VALUE = vector<long long int>(((long long int)(mpi_rem.MPI_VALUE).size()), 0); long long int mpi_num_pos = ((long long int)(mpi_num.MPI_VALUE).size()) - 1; long long int mpi_num_n = mpi_num.MPI_VALUE[mpi_num_pos]; if (mpi_num_n * 1000000 < 1000000000000000000ll / 1000000 && 1 <= mpi_num_pos) { mpi_num_n = mpi_num_n * 1000000 + mpi_num.MPI_VALUE[--mpi_num_pos]; } while (!mpi_abs_gt(mpi_rem, mpi_num)) { long long int mpi_rem_pos = ((long long int)(mpi_rem.MPI_VALUE).size()) - 1; long long int mpi_rem_n = mpi_rem.MPI_VALUE[mpi_rem_pos]; while (mpi_rem_n < mpi_num_n) { mpi_rem_n = mpi_rem_n * 1000000 + mpi_rem.MPI_VALUE[--mpi_rem_pos]; } long long int mpi_tmp = mpi_rem_n / mpi_num_n; long long int mpi_dif = mpi_rem_pos - mpi_num_pos; while (!mpi_can_sub(mpi_rem, mpi_num, mpi_tmp, mpi_dif)) mpi_tmp--; if (mpi_tmp == 0) { mpi_rem_n = mpi_rem_n * 1000000 + mpi_rem.MPI_VALUE[--mpi_rem_pos]; mpi_tmp = mpi_rem_n / mpi_num_n; mpi_dif = mpi_rem_pos - mpi_num_pos; while (!mpi_can_sub(mpi_rem, mpi_num, mpi_tmp, mpi_dif)) mpi_tmp--; } mpi_subst(mpi_rem, mpi_num, mpi_tmp, mpi_dif); mpi_ans.MPI_VALUE[mpi_dif] += mpi_tmp; mpi_reform(mpi_rem); } if (!is_div) return mpi_rem; mpi_add_mul_reform(mpi_ans); return mpi_ans; } MPI operator/(const MPI &mpi_var) const { bool b0 = MPI_SIGN, b1 = mpi_var.MPI_SIGN; if (!b0 && !b1) return mpi_abs_div(*this, mpi_var, true); if (b0 && b1) return mpi_abs_div(*this, mpi_var, true); MPI mpi_res = mpi_abs_div(*this, mpi_var, true); mpi_res.MPI_SIGN = !mpi_res.MPI_SIGN; return mpi_res; } MPI operator%(const MPI &mpi_var) const { bool b0 = MPI_SIGN; if (!b0) return mpi_abs_div(*this, mpi_var, false); MPI mpi_res = mpi_abs_div(*this, mpi_var, false); mpi_res.MPI_SIGN = !mpi_res.MPI_SIGN; return mpi_res; } bool operator<(const MPI &mpi_var) const { bool b0 = MPI_SIGN, b1 = mpi_var.MPI_SIGN; if (!b0 && !b1) return mpi_abs_gt(*this, mpi_var); if (b0 && b1) return mpi_abs_sl(*this, mpi_var); if (((long long int)(this->MPI_VALUE).size()) == 1 && ((long long int)(mpi_var.MPI_VALUE).size()) == 1) { if (this->MPI_VALUE.back() == 0 && mpi_var.MPI_VALUE.back() == 0) return true; } if (b0 && !b1) return true; if (!b0 && b1) return false; } bool operator>(const MPI &mpi_var) const { bool b0 = MPI_SIGN, b1 = mpi_var.MPI_SIGN; if (!b0 && !b1) return mpi_abs_sl(*this, mpi_var); if (b0 && b1) return mpi_abs_gt(*this, mpi_var); if (((long long int)(this->MPI_VALUE).size()) == 1 && ((long long int)(mpi_var.MPI_VALUE).size()) == 1) { if (this->MPI_VALUE.back() == 0 && mpi_var.MPI_VALUE.back() == 0) return true; } if (b0 && !b1) return false; if (!b0 && b1) return true; } bool operator==(const MPI &mpi_var) const { bool b0 = MPI_SIGN, b1 = mpi_var.MPI_SIGN; if (b0 && b1) return mpi_abs_eq(*this, mpi_var); if (!b0 && !b1) return mpi_abs_eq(*this, mpi_var); if (((long long int)(this->MPI_VALUE).size()) == 1 && ((long long int)(mpi_var.MPI_VALUE).size()) == 1) { if (this->MPI_VALUE.back() == 0 && mpi_var.MPI_VALUE.back() == 0) return true; } return false; } bool operator>=(const MPI &mpi_var) const { return !(*this < mpi_var); } bool operator<=(const MPI &mpi_var) const { return !(*this > mpi_var); } bool operator!=(const MPI &mpi_var) const { return !(*this == mpi_var); } void operator+=(const MPI &mpi_var) { *this = *this + mpi_var; } void operator-=(const MPI &mpi_var) { *this = *this - mpi_var; } void operator*=(const MPI &mpi_var) { *this = *this * mpi_var; } void operator/=(const MPI &mpi_var) { *this = *this / mpi_var; } void operator%=(const MPI &mpi_var) { *this = *this % mpi_var; } friend bool operator>(long long int mpi_li, const MPI &mpi_var) { return MPI(mpi_li) > mpi_var; } friend bool operator<(long long int mpi_li, const MPI &mpi_var) { return MPI(mpi_li) < mpi_var; } friend bool operator>=(long long int mpi_li, const MPI &mpi_var) { return MPI(mpi_li) >= mpi_var; } friend bool operator<=(long long int mpi_li, const MPI &mpi_var) { return MPI(mpi_li) <= mpi_var; } friend bool operator!=(long long int mpi_li, const MPI &mpi_var) { return MPI(mpi_li) != mpi_var; } friend bool operator==(long long int mpi_li, const MPI &mpi_var) { return MPI(mpi_li) == mpi_var; } MPI operator--() { *this = *this - MPI(1); return *this; } MPI operator++() { *this = *this + MPI(1); return *this; } MPI operator++(int mpi_i) { MPI mpi_res = *this; *this = *this + MPI(1); return mpi_res; } MPI operator--(int mpi_i) { MPI mpi_res = *this; *this = *this - MPI(1); return mpi_res; } MPI operator-() { MPI mpi_res = *this; mpi_res.MPI_SIGN = !mpi_res.MPI_SIGN; return mpi_res; } static bool mpi_abs_gt(const MPI &mpi0, const MPI &mpi1) { if (((long long int)(mpi0.MPI_VALUE).size()) == ((long long int)(mpi1.MPI_VALUE).size())) { for (long long int i = ((long long int)(mpi0.MPI_VALUE).size()) - 1; 0 <= i; i--) { if (mpi0.MPI_VALUE[i] != mpi1.MPI_VALUE[i]) { return mpi0.MPI_VALUE[i] < mpi1.MPI_VALUE[i]; } } } return ((long long int)(mpi0.MPI_VALUE).size()) < ((long long int)(mpi1.MPI_VALUE).size()); } static bool mpi_abs_sl(const MPI &mpi0, const MPI &mpi1) { if (((long long int)(mpi0.MPI_VALUE).size()) == ((long long int)(mpi1.MPI_VALUE).size())) { for (long long int i = ((long long int)(mpi0.MPI_VALUE).size()) - 1; 0 <= i; i--) { if (mpi0.MPI_VALUE[i] != mpi1.MPI_VALUE[i]) { return mpi0.MPI_VALUE[i] > mpi1.MPI_VALUE[i]; } } } return ((long long int)(mpi0.MPI_VALUE).size()) > ((long long int)(mpi1.MPI_VALUE).size()); } static bool mpi_abs_eq(const MPI &mpi0, const MPI &mpi1) { if (((long long int)(mpi0.MPI_VALUE).size()) != ((long long int)(mpi1.MPI_VALUE).size())) return false; for (long long int i = 0; i < ((long long int)(((long long int)(mpi0.MPI_VALUE).size()))); i++) { if (mpi0.MPI_VALUE[i] != mpi1.MPI_VALUE[i]) return false; } return true; } private: static void mpi_reform_vec(vector<long long int> &mpi_vec) { if (((long long int)(mpi_vec).size()) == 0) mpi_vec.push_back(0); while (1 < ((long long int)(mpi_vec).size()) && mpi_vec.back() == 0) mpi_vec.pop_back(); } static void mpi_add_mul_reform_vec(vector<long long int> &mpi_vec) { long long int carry = 0; for (long long int i = 0; i < ((long long int)(((long long int)(mpi_vec).size()))); i++) { mpi_vec[i] += carry; carry = mpi_vec[i] / 1000000; mpi_vec[i] %= 1000000; } mpi_vec.push_back(carry); mpi_reform_vec(mpi_vec); } static void mpi_reform(MPI &mpi_var) { mpi_reform_vec(mpi_var.MPI_VALUE); if (((long long int)(mpi_var.MPI_VALUE).size()) == 1 && mpi_var.MPI_VALUE[0] == 0) mpi_var.MPI_SIGN = false; } static void mpi_add_mul_reform(MPI &mpi_var) { mpi_add_mul_reform_vec(mpi_var.MPI_VALUE); if (((long long int)(mpi_var.MPI_VALUE).size()) == 1 && mpi_var.MPI_VALUE[0] == 0) mpi_var.MPI_SIGN = false; } }; class IRN { public: MPI IRN_DEN; MPI IRN_NUM; bool IRN_SIGN; IRN() { IRN_DEN = 0; IRN_NUM = 1; IRN_SIGN = false; } IRN(string irn_str0, string irn_str1) { IRN_DEN = irn_str0; IRN_NUM = irn_str1; IRN_SIGN = false; if (IRN_DEN < 0) IRN_SIGN = !IRN_SIGN; if (IRN_NUM < 0) IRN_SIGN = !IRN_SIGN; IRN_DEN.MPI_SIGN = false; IRN_NUM.MPI_SIGN = false; irn_reduct(*this); } IRN(long long int irn_li0, long long int irn_li1) { IRN_DEN = irn_li0; IRN_NUM = irn_li1; IRN_SIGN = false; if (IRN_DEN < 0) IRN_SIGN = !IRN_SIGN; if (IRN_NUM < 0) IRN_SIGN = !IRN_SIGN; IRN_DEN.MPI_SIGN = false; IRN_NUM.MPI_SIGN = false; irn_reduct(*this); } IRN(long long int irn_li) { IRN_DEN = irn_li; IRN_NUM = 1; IRN_SIGN = false; } IRN(string irn_str) { IRN_DEN = irn_str; IRN_NUM = 1; IRN_SIGN = false; } string to_string() const { if (IRN_SIGN && IRN_DEN != 0) return "-" + IRN_DEN.to_string() + "/" + IRN_NUM.to_string(); return IRN_DEN.to_string() + "/" + IRN_NUM.to_string(); } static MPI irn_mpi_gcd(MPI mpi0, MPI mpi1) { MPI mpi_res = 1; if (mpi0 == 0 || mpi1 == 0) return MPI(1); for (MPI i = 2; i * i <= min(mpi0, mpi1); i++) { while (true) { if (mpi0 % i != 0) break; if (mpi1 % i != 0) break; mpi0 /= i; mpi1 /= i; mpi_res *= i; } while (mpi0 % i == 0) mpi0 /= i; while (mpi1 % i == 0) mpi1 /= i; } if (mpi0 % min(mpi0, mpi1) != 0) return mpi_res; if (mpi1 % min(mpi0, mpi1) != 0) return mpi_res; return mpi_res * min(mpi0, mpi1); } void irn_reduct(IRN &irn_var) const { if (irn_var.IRN_DEN == 0) { irn_var.IRN_NUM = 1; irn_var.IRN_SIGN = false; return; } if (irn_var.IRN_DEN.MPI_SIGN) irn_var.IRN_SIGN = !irn_var.IRN_SIGN; if (irn_var.IRN_NUM.MPI_SIGN) irn_var.IRN_SIGN = !irn_var.IRN_SIGN; irn_var.IRN_DEN.MPI_SIGN = false; irn_var.IRN_NUM.MPI_SIGN = false; MPI irn_t = irn_mpi_gcd(irn_var.IRN_NUM, irn_var.IRN_DEN); irn_var.IRN_NUM /= irn_t; irn_var.IRN_DEN /= irn_t; } IRN irn_mul(const IRN &irn0, const IRN &irn1) const { IRN irn_res(1, 1); MPI irn_t = irn_mpi_gcd(irn0.IRN_DEN, irn1.IRN_NUM); irn_res.IRN_DEN = irn0.IRN_DEN / irn_t; irn_res.IRN_NUM = irn1.IRN_NUM / irn_t; irn_t = irn_mpi_gcd(irn0.IRN_NUM, irn1.IRN_DEN); irn_res.IRN_DEN *= irn1.IRN_DEN / irn_t; irn_res.IRN_NUM *= irn0.IRN_NUM / irn_t; if (irn1.IRN_SIGN) irn_res.IRN_SIGN = !irn_res.IRN_SIGN; if (irn0.IRN_SIGN) irn_res.IRN_SIGN = !irn_res.IRN_SIGN; if (irn_res.IRN_DEN == 0) { irn_res.IRN_NUM = 1; irn_res.IRN_SIGN = false; } return irn_res; } IRN irn_div(const IRN &irn0, const IRN &irn1) const { IRN irn_res(1, 1); MPI irn_t = irn_mpi_gcd(irn0.IRN_DEN, irn1.IRN_DEN); irn_res.IRN_DEN = irn0.IRN_DEN / irn_t; irn_res.IRN_NUM = irn1.IRN_DEN / irn_t; irn_t = irn_mpi_gcd(irn0.IRN_NUM, irn1.IRN_NUM); irn_res.IRN_DEN *= irn1.IRN_NUM / irn_t; irn_res.IRN_NUM *= irn0.IRN_NUM / irn_t; if (irn1.IRN_SIGN) irn_res.IRN_SIGN = !irn_res.IRN_SIGN; if (irn0.IRN_SIGN) irn_res.IRN_SIGN = !irn_res.IRN_SIGN; if (irn_res.IRN_DEN == 0) { irn_res.IRN_NUM = 1; irn_res.IRN_SIGN = false; } return irn_res; } IRN irn_abs_add(const IRN &irn0, const IRN &irn1) const { IRN irn_res(0); if (irn0.IRN_NUM == irn1.IRN_NUM) { irn_res.IRN_DEN = irn0.IRN_DEN + irn1.IRN_DEN; irn_res.IRN_NUM = irn0.IRN_NUM; irn_reduct(irn_res); return irn_res; } irn_res.IRN_NUM = irn0.IRN_NUM * irn1.IRN_NUM; irn_res.IRN_DEN = irn0.IRN_DEN * irn1.IRN_NUM; irn_res.IRN_DEN += irn1.IRN_DEN * irn0.IRN_NUM; irn_reduct(irn_res); return irn_res; } IRN irn_abs_sub(const IRN &irn0, const IRN &irn1) const { IRN irn_res(0); if (irn0.IRN_NUM == irn1.IRN_NUM) { irn_res.IRN_DEN = irn0.IRN_DEN - irn1.IRN_DEN; irn_res.IRN_NUM = irn0.IRN_NUM; irn_reduct(irn_res); return irn_res; } irn_res.IRN_NUM = irn0.IRN_NUM * irn1.IRN_NUM; irn_res.IRN_DEN = irn0.IRN_DEN * irn1.IRN_NUM; irn_res.IRN_DEN -= irn1.IRN_DEN * irn0.IRN_NUM; irn_reduct(irn_res); return irn_res; } IRN irn_add(const IRN &irn0, const IRN &irn1) const { if (irn0.IRN_SIGN && irn1.IRN_SIGN) { IRN irn_res = irn_abs_add(irn0, irn1); irn_res.IRN_SIGN = !irn_res.IRN_SIGN; return irn_res; } if (!irn0.IRN_SIGN && !irn1.IRN_SIGN) return irn_abs_add(irn0, irn1); IRN irn_res; if (!irn0.IRN_SIGN && irn1.IRN_SIGN) irn_res = irn_abs_sub(irn0, irn1); if (irn0.IRN_SIGN && !irn1.IRN_SIGN) irn_res = irn_abs_sub(irn1, irn0); if (irn_res.IRN_DEN.MPI_SIGN) { irn_res.IRN_DEN.MPI_SIGN = false; irn_res.IRN_SIGN = true; } return irn_res; } IRN irn_sub(const IRN &irn0, const IRN &irn1) const { if (!irn0.IRN_SIGN && irn1.IRN_SIGN) return irn_abs_add(irn0, irn1); if (irn0.IRN_SIGN && !irn1.IRN_SIGN) { IRN irn_res = irn_abs_add(irn0, irn1); irn_res.IRN_SIGN = !irn_res.IRN_SIGN; return irn_res; } IRN irn_res; if (irn0.IRN_SIGN && irn1.IRN_SIGN) { irn_res = irn_abs_sub(irn0, irn1); irn_res.IRN_SIGN = !irn_res.IRN_SIGN; } if (!irn0.IRN_SIGN && !irn1.IRN_SIGN) { irn_res = irn_abs_sub(irn0, irn1); } if (irn_res.IRN_DEN.MPI_SIGN) { irn_res.IRN_DEN.MPI_SIGN = false; irn_res.IRN_SIGN = true; } return irn_res; } bool operator<(const IRN &irn_var) const { if (this->IRN_DEN == 0 && irn_var.IRN_DEN == 0) return false; bool b0 = this->IRN_SIGN, b1 = irn_var.IRN_SIGN; if (b0 && !b1) return true; if (!b1 && b0) return false; MPI left = this->IRN_DEN * irn_var.IRN_NUM; MPI right = irn_var.IRN_DEN * this->IRN_NUM; if (!b0 && !b1) return left < right; return right < left; } bool operator>(const IRN &irn_var) const { if (this->IRN_DEN == 0 && irn_var.IRN_DEN == 0) return false; bool b0 = this->IRN_SIGN, b1 = irn_var.IRN_SIGN; if (b0 && !b1) return false; if (!b0 && b1) return true; MPI left = this->IRN_DEN * irn_var.IRN_NUM; MPI right = irn_var.IRN_DEN * this->IRN_NUM; if (!b0 && !b1) return left > right; return right < left; } bool operator==(const IRN &irn_var) const { if (this->IRN_DEN == 0 && irn_var.IRN_DEN == 0) return true; if (this->IRN_SIGN && !irn_var.IRN_SIGN) return false; if (!this->IRN_SIGN && irn_var.IRN_SIGN) return false; return this->IRN_DEN == irn_var.IRN_DEN && this->IRN_NUM == irn_var.IRN_NUM; } IRN operator+(const IRN &irn_var) const { return irn_add(*this, irn_var); } IRN operator-(const IRN &irn_var) const { return irn_sub(*this, irn_var); } IRN operator/(const IRN &irn_var) const { return irn_div(*this, irn_var); } IRN operator*(const IRN &irn_var) const { return irn_mul(*this, irn_var); } void operator+=(const IRN &irn_var) { *this = *this + irn_var; } void operator-=(const IRN &irn_var) { *this = *this - irn_var; } void operator*=(const IRN &irn_var) { *this = *this * irn_var; } void operator/=(const IRN &irn_var) { *this = *this / irn_var; } IRN operator<=(const IRN &irn_var) const { return !(irn_var < *this); } IRN operator>=(const IRN &irn_var) const { return !(*this < irn_var); } IRN operator!=(const IRN &irn_var) const { return !(*this == irn_var); } friend std::ostream &operator<<(std::ostream &os, const IRN &irn_var) { os << irn_var.to_string(); return os; } private: }; string mp[55]; long long int dx[] = {1, 0, -1, 0}; long long int dy[] = {0, 1, 0, -1}; int main() { long long int n, m, k, sx, sy, gx, gy; cin >> n >> m >> k; for (long long int i = 0; i < ((long long int)(n)); i++) cin >> mp[i]; for (long long int i = 0; i < ((long long int)(n)); i++) for (long long int j = 0; j < ((long long int)(m)); j++) if (mp[i][j] == 'S') sx = i, sy = j; for (long long int i = 0; i < ((long long int)(n)); i++) for (long long int j = 0; j < ((long long int)(m)); j++) if (mp[i][j] == 'T') gx = i, gy = j; set<pair<long long int, pair<long long int, long long int> > > used; priority_queue< pair<pair<long long int, string>, pair<long long int, pair<long long int, long long int> > >, vector<pair<pair<long long int, string>, pair<long long int, pair<long long int, long long int> > > >, greater< pair<pair<long long int, string>, pair<long long int, pair<long long int, long long int> > > > > q; q.push(make_pair(make_pair(0, ""), make_pair(0, make_pair(sx, sy)))); while (((long long int)(q).size())) { long long int mask = q.top().second.first; long long int x = q.top().second.second.first; long long int y = q.top().second.second.second; string str = q.top().first.second; q.pop(); bool ok = true; { long long int tmp = mask; do { if (used.find(make_pair(tmp, make_pair(x, y))) != used.end()) ok = false; tmp = (tmp - 1) & mask; } while (ok && tmp != mask); } if (!ok) continue; used.insert(make_pair(mask, make_pair(x, y))); for (long long int i = 0; i < ((long long int)(4)); i++) { long long int xx = x + dx[i]; long long int yy = y + dy[i]; if (xx < 0 || n <= xx || yy < 0 || m <= yy) continue; if (mp[xx][yy] == 'T') { cout << str << endl; return 0; } if (mp[xx][yy] == 'S') continue; string next = str + string(1, mp[xx][yy]); long long int nmask = mask | (1ll << (long long int)(mp[xx][yy] - 'a')); if (k < __builtin_popcountll(nmask)) continue; q.push(make_pair(make_pair(((long long int)(next).size()), next), make_pair(nmask, make_pair(xx, yy)))); } } cout << -1 << endl; }
#include <bits/stdc++.h> using namespace std; template <typename S, typename T> void fill_(S& buf, T x) { fill(reinterpret_cast<T*>(&buf), reinterpret_cast<T*>(&buf) + sizeof(buf) / sizeof(T), x); } template <typename T, int N> inline int countof(const T (&)[N]) { return N; } template <typename T> inline vector<T>& operator+=(vector<T>& ret, const T& x) { ret.push_back(x); return ret; } int begin___ = 0, end___ = 0; int fifo___[(1000000)]; int originalBoard[(50) + 8][(50) + 8]; int board[(50) + 8][(50) + 8]; int distances[(50) + 8][(50) + 8]; int H, W, K; int best = (INT_MAX); int dys[] = {-1, 0, 0, 1}; int dxs[] = {0, -1, 1, 0}; int y0_, x0_, ye_, xe_; vector<vector<int>> cxs, cys; string ret; bool find_pos(int& y, int& x, const int c) { for (int i = int(0), CNT_i = int(H); i < CNT_i; ++i) for (int j = int(0), CNT_j = int(W); j < CNT_j; ++j) if (originalBoard[i][j] == c) { y = i; x = j; return true; } return false; } inline bool in_range(const int y, const int x) { return 0 <= y && y < H && 0 <= x && x < W && board[y][x] != '#'; } bool bfs() { fill_(distances, (INT_MAX)); (begin___ = end___ = 0); (fifo___[end___++] = (((((0) & 0x3FFF) << 18) | (((ye_)&0x1FF) << 9) | ((xe_)&0x1FF)))); while (!(begin___ == end___)) { int S_cyx = ((fifo___[begin___++])), c = ((S_cyx) >> 18 & 0x3FFF), y = ((S_cyx) >> 9 & 0x1FF), x = ((S_cyx)&0x1FF); ; if (distances[y][x] != (INT_MAX)) continue; distances[y][x] = c; if (y == y0_ && x == x0_) continue; for (int i = int(0), CNT_i = int(countof(dys)); i < CNT_i; ++i) { const int y_ = y + dys[i], x_ = x + dxs[i]; if (!in_range(y_, x_)) continue; (fifo___[end___++] = (((((c + 1) & 0x3FFF) << 18) | (((y_)&0x1FF) << 9) | ((x_)&0x1FF)))); } } return distances[y0_][x0_] != (INT_MAX); } void route() { const int d = distances[y0_][x0_]; if (d > best) { return; } else { string r; assert(d != (INT_MAX)); vector<int> xs; r.clear(); (begin___ = end___ = 0); (fifo___[end___++] = ((((('S') & 0x3FFF) << 18) | (((y0_)&0x1FF) << 9) | ((x0_)&0x1FF)))); for (int n = d - 1; n > 0; --n) { xs.clear(); while (!(begin___ == end___)) { int S_cyx = ((fifo___[begin___++])), c = ((S_cyx) >> 18 & 0x3FFF), y = ((S_cyx) >> 9 & 0x1FF), x = ((S_cyx)&0x1FF); ; for (int i = int(0), CNT_i = int(countof(dys)); i < CNT_i; ++i) { const int y_ = y + dys[i], x_ = x + dxs[i]; if (!in_range(y_, x_) || distances[y_][x_] != n) continue; xs += ((((board[y_][x_]) & 0x3FFF) << 18) | (((y_)&0x1FF) << 9) | ((x_)&0x1FF)); } } (begin___ = end___ = 0); sort((xs).begin(), (xs).end()); const int L = unique((xs).begin(), (xs).end()) - xs.begin(); int S_cy_x_ = (xs[0]), c_ = ((S_cy_x_) >> 18 & 0x3FFF), y_ = ((S_cy_x_) >> 9 & 0x1FF), x_ = ((S_cy_x_)&0x1FF); ; for (int i = int(0), CNT_i = int(L); i < CNT_i; ++i) { if (((xs[i]) >> 18 & 0x3FFF) == c_) (fifo___[end___++] = (xs[i])); else break; } r += c_; }; if (d < best) { best = d; ret = r; } else { ret = min(ret, r); } } } void dfs(const int k, int next) { if (k == 0) { if (bfs()) route(); } else { for (int c = next; c <= int('z'); ++c) { const vector<int>(&ys) = cys[c], (&xs) = cxs[c]; for (int i = int(0), CNT_i = int(int((ys).size())); i < CNT_i; ++i) board[ys[i]][xs[i]] = c; dfs(k - 1, c + 1); for (int i = int(0), CNT_i = int(int((ys).size())); i < CNT_i; ++i) board[ys[i]][xs[i]] = '#'; } } } void init() { find_pos(y0_, x0_, 'S'); find_pos(ye_, xe_, 'T'); fill_(board, int('#')); board[y0_][x0_] = 'S'; board[ye_][xe_] = 'T'; fill_(distances, (INT_MAX)); cys.assign(int('z') + 10, vector<int>()); cxs.assign(int('z') + 10, vector<int>()); for (int i = int(0), CNT_i = int(H); i < CNT_i; ++i) for (int j = int(0), CNT_j = int(W); j < CNT_j; ++j) { cys[originalBoard[i][j]] += i; cxs[originalBoard[i][j]] += j; } } int main(int argc, char* argv[]) { string s; cin >> H >> W >> K; for (int i = int(0), CNT_i = int(H); i < CNT_i; ++i) { cin >> s; for (int j = int(0), CNT_j = int(int((s).size())); j < CNT_j; ++j) originalBoard[i][j] = s[j]; } init(); dfs(K, 'a'); if (best == (INT_MAX)) cout << -1 << endl; else cout << ret << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int n, m; int k; char str[55][55]; int sr, sc; int er, ec; string cur; bool can[26]; int am = 0; int mark[55][55]; int dist[55][55]; int dx[] = {1, -1, 0, 0}; int dy[] = {0, 0, 1, -1}; int qhead, qtail; int q[55 * 55 * 4]; int nqtail; int nq[55 * 55 * 4]; int go(int r, int c) { qhead = qtail = 0; mark[r][c] = am; dist[r][c] = 0; q[qtail++] = r; q[qtail++] = c; while (qhead < qtail) { int cr = q[qhead++]; int cc = q[qhead++]; if (str[cr][cc] == 'S') return dist[cr][cc]; for (int dir = 0; dir < 4; ++dir) { int nr = cr + dx[dir]; int nc = cc + dy[dir]; if (nr < 0 || nr >= n || nc < 0 || nc >= m) continue; if (mark[nr][nc] == am) continue; if (str[nr][nc] != 'S' && (str[nr][nc] == 'T' || !can[str[nr][nc] - 'a'])) continue; mark[nr][nc] = am; dist[nr][nc] = dist[cr][cc] + 1; q[qtail++] = nr; q[qtail++] = nc; } } return 987654321; } void rec(int r, int c) { qhead = qtail = 0; nqtail = 0; q[qtail++] = r; q[qtail++] = c; mark[r][c] = am; cur = ""; for (int stp = 0; stp < dist[r][c] - 1; ++stp) { int best = 255; for (int i = 0; i < qtail; i += 2) { int cr = q[i]; int cc = q[i + 1]; for (int dir = 0; dir < 4; ++dir) { int nr = cr + dx[dir]; int nc = cc + dy[dir]; if (mark[nr][nc] == am) continue; if (nr < 0 || nr >= n || nc < 0 || nc >= m) continue; if (dist[nr][nc] != dist[cr][cc] - 1) continue; if (str[nr][nc] != 'T' && (str[nr][nc] == 'S' || !can[str[nr][nc] - 'a'])) continue; best = min(best, (int)str[nr][nc]); } } cur += char(best); for (int i = 0; i < qtail; i += 2) { int cr = q[i]; int cc = q[i + 1]; for (int dir = 0; dir < 4; ++dir) { int nr = cr + dx[dir]; int nc = cc + dy[dir]; if (mark[nr][nc] == am) continue; if (nr < 0 || nr >= n || nc < 0 || nc >= m) continue; if (dist[nr][nc] != dist[cr][cc] - 1) continue; if (str[nr][nc] != 'T' && (str[nr][nc] == 'S' || !can[str[nr][nc] - 'a'])) continue; if (best == str[nr][nc]) { mark[nr][nc] = am; nq[nqtail++] = nr; nq[nqtail++] = nc; } } } for (int i = 0; i < nqtail; ++i) { q[i] = nq[i]; } qtail = nqtail; nqtail = 0; } } int main() { cin >> n >> m >> k; for (int i = 0; i < n; ++i) { cin >> str[i]; for (int j = 0; j < m; ++j) if (str[i][j] == 'S') { sr = i; sc = j; } else if (str[i][j] == 'T') { er = i; ec = j; } } int dist = 987654321; string res = ""; memset(can, 0, sizeof(can)); memset(mark, -1, sizeof(mark)); for (int a = 0; a < 26; ++a) { for (int b = a; b < 26; ++b) { for (int c = b; c < 26; ++c) { for (int d = c; d < 26; ++d) { int cnt = 1; if (b != a) ++cnt; if (c != b) ++cnt; if (d != c) ++cnt; if (cnt > k) continue; ++am; cur = ""; can[a] = 1; can[b] = 1; can[c] = 1; can[d] = 1; int ndist = go(er, ec); if (ndist <= dist && ndist != 987654321) { ++am; rec(sr, sc); if (ndist < dist || ndist == dist && cur < res) { dist = ndist; res = cur; } } can[a] = 0; can[b] = 0; can[c] = 0; can[d] = 0; } } } } if (dist == 987654321) cout << "-1" << endl; else cout << res << endl; return 0; }
#include <bits/stdc++.h> using namespace std; struct node { int x, y, g, h, t; string p; bool operator<(const node& obj) const { if (g + h != obj.g + obj.h) return g + h > obj.g + obj.h; return p > obj.p; } }; const int dx[4] = {-1, 0, 1, 0}, dy[4] = {0, -1, 0, 1}; priority_queue<node> q; set<pair<pair<int, int>, int> > v; char a[51][55]; int main(void) { int n, m, s, sx, sy, tx, ty; scanf("%d %d %d", &n, &m, &s); for (int i = 1; i <= n; ++i) { scanf("%s", a[i] + 1); for (int j = 1; j <= m; ++j) { if (a[i][j] == 'S') { sx = i; sy = j; } else if (a[i][j] == 'T') { tx = i; ty = j; } } } node b; b.x = sx; b.y = sy; b.g = 0; b.h = abs(sx - tx) + abs(sy - ty); b.t = 0; b.p = ""; q.push(b); while (!q.empty()) { b = q.top(); if (b.h == 0) break; q.pop(); pair<pair<int, int>, int> temp = make_pair(make_pair(b.x, b.y), b.t); if (v.count(temp) > 0) continue; v.insert(temp); for (int k = 0; k < 4; ++k) { int i = b.x + dx[k], j = b.y + dy[k]; if ((i < 1) || (i > n) || (j < 1) || (j > m) || (a[i][j] == 'S')) continue; node e = b; e.x += dx[k]; e.y += dy[k]; ++e.g; e.h = abs(i - tx) + abs(j - ty); if (a[i][j] == 'T') { q.push(e); continue; } e.t |= (1 << (a[i][j] - 'a')); int temp = e.t, c = 0; while (temp > 0) { c += temp % 2; temp /= 2; } if (c > s) continue; e.p += a[i][j]; q.push(e); } } if (!q.empty()) cout << q.top().p << endl; else printf("-1\n"); return 0; }
#include <bits/stdc++.h> using namespace std; int n, m, k; char board[3000][3000]; int si, sj, fi, fj; bool found; string ans; bool outside(int x, int y) { return (x < 1 || x > n || y < 1 || y > m); } int bits(int x) { if (x == 0) return 0; return bits(x / 2) + x % 2; } struct node { int x, y, mask; string way; bool operator<(const node &other) const { if (way.length() != other.way.length()) return way.length() > other.way.length(); return way > other.way; } }; int sx, sy; set<int> done[55][55]; priority_queue<node> qu; vector<int> dx, dy; int smask[55][55]; int main() { ios_base::sync_with_stdio(0); dx.push_back(0); dx.push_back(0); dx.push_back(1); dx.push_back(-1); dy.push_back(-1); dy.push_back(1); dy.push_back(0); dy.push_back(0); cin >> n >> m >> k; for (int i = 1; i <= n; i++) { string st; cin >> st; for (int j = 1; j <= m; j++) { board[i][j] = st[j - 1]; if (board[i][j] == 'S') { si = i; sj = j; } if (board[i][j] == 'T') { fi = i; fj = j; } } } node temp; temp.x = si; temp.y = sj; temp.mask = 0; temp.way = ""; qu.push(temp); found = 0; while (qu.size()) { node cur = qu.top(); qu.pop(); int qx = cur.x; int qy = cur.y; if (found) break; for (int dir = 0; dir < 4; dir++) { int nx = qx + dx[dir]; int ny = qy + dy[dir]; if (outside(nx, ny)) continue; if (board[nx][ny] == 'S') continue; if (board[nx][ny] == 'T' && found == 0) { found = 1; ans = cur.way; break; } int nmask = (cur.mask | (1 << (board[nx][ny] - 'a'))); if (bits(nmask) > k) continue; if (done[nx][ny].find(nmask) != done[nx][ny].end()) continue; if ((smask[nx][ny] & nmask) == smask[nx][ny] && smask[nx][ny] > 0) continue; smask[nx][ny] = nmask; done[nx][ny].insert(nmask); temp.x = nx; temp.y = ny; temp.mask = nmask; temp.way = cur.way + board[nx][ny]; qu.push(temp); } } if (found == 0) cout << -1 << endl; else cout << ans << endl; return 0; }
#include <bits/stdc++.h> using namespace std; char _; const int maxN = 50 + 5; const int mod = 1000 * 1000 * 1000 + 7; const int base = 701; const int SQ = 330; const int maxL = 302; int dx[] = {-1, 1, 0, 0}; int dy[] = {0, 0, -1, 1}; char a[maxN][maxN]; int sx, sy, tx, ty; int mark[26], cnt; string res; int n, m, k; int dis[maxN][maxN]; pair<int, int> q[2500]; bool is_ok(int x, int y) { if (x < 0 || y < 0 || n <= x || m <= y) return false; return true; } pair<int, int> par[maxN][maxN]; int proi[maxN][maxN]; bool cmp(const pair<int, int> &p, const pair<int, int> &q) { if (a[p.first][p.second] != a[q.first][q.second]) return (a[p.first][p.second] < a[q.first][q.second]); pair<int, int> pp = par[p.first][p.second], qq = par[q.first][q.second]; return (proi[pp.first][pp.second] < proi[qq.first][qq.second]); } string ss; void solve(int x, int y) { if (x == tx && y == ty) return; if (x != sx || y != sy) ss += a[x][y]; solve(par[x][y].first, par[x][y].second); } void check() { memset(dis, 0, sizeof dis); memset(proi, 0, sizeof proi); memset(par, -1, sizeof par); dis[tx][ty] = 1; int st = 0, en = 0; q[en++] = {tx, ty}; while (st < en) { if (st && dis[q[st].first][q[st].second] > dis[q[st - 1].first][q[st - 1].second]) { sort(q + st, q + en, cmp); int cnt = 0; for (int i = st + 1; i < en; i++) { if (cmp(q[i - 1], q[i])) cnt++; proi[q[i].first][q[i].second] = cnt; } } int x = q[st].first, y = q[st].second; st++; if (make_pair(x, y) == make_pair(sx, sy)) break; for (int i = 0; i < 4; i++) { int v = x + dx[i], u = y + dy[i]; if (is_ok(v, u) && dis[v][u] == 0 && (a[v][u] == 'S' || mark[a[v][u] - 'a'] == 1)) { dis[v][u] = dis[x][y] + 1; q[en++] = {v, u}; par[v][u] = {x, y}; } } } if (dis[sx][sy] == 0) return; if (dis[sx][sy] - 2 > (int)res.size()) return; ss = ""; solve(sx, sy); if (dis[sx][sy] - 2 < (int)res.size()) res = ss; else res = min(res, ss); } void bt(int t) { if (t == 26) return; if (cnt < k) { mark[t] = 1; cnt++; check(); bt(t + 1); mark[t] = 0; cnt--; } bt(t + 1); } int32_t main() { ios::sync_with_stdio(0); cin.tie(0); cin >> n >> m >> k; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { cin >> a[i][j]; if (a[i][j] == 'S') sx = i, sy = j; if (a[i][j] == 'T') tx = i, ty = j; } res = string(3000, 'z'); bt(0); if (res.size() == 3000) { cout << -1 << endl; return 0; } cout << res << endl; return 0; }
#include <bits/stdc++.h> #pragma comment(linker, "/STACK:256000000") using namespace std; const int INF = 1000 * 1000 * 1000; char tbl[55][55]; bool ap[55][55]; int dst[55][55]; string p[55][55]; bool got[55]; int dx[4] = {1, 0, -1, 0}; int dy[4] = {0, -1, 0, 1}; string path; bool SUKASUKA; int N, M, K; pair<int, int> s, t; bool checkPos(int x, int y) { return x >= 0 && x < N && y >= 0 && y < M && ap[x][y]; } void solve() { if (path.empty()) { path.resize(N * M + 1, 'z' + 1); } vector<char> gc; for (int i = (0); i < (26); ++i) if (got[i]) { gc.push_back(char('a' + i)); } for (int i = (0); i < (N); ++i) for (int j = (0); j < (M); ++j) { ap[i][j] = false; for (int k = (0); k < ((int)gc.size()); ++k) if (tbl[i][j] == gc[k]) { ap[i][j] = true; } } ap[s.first][s.second] = ap[t.first][t.second] = true; for (int i = (0); i < (N); ++i) for (int j = (0); j < (M); ++j) { dst[i][j] = INF; p[i][j] = ""; } dst[s.first][s.second] = 0; queue<pair<int, int> > q; q.push(s); while (!q.empty()) { pair<int, int> now = q.front(); q.pop(); for (int k = (0); k < (4); ++k) { int x = now.first + dx[k], y = now.second + dy[k]; if (checkPos(x, y)) if (dst[x][y] > dst[now.first][now.second] + 1) { dst[x][y] = dst[now.first][now.second] + 1; p[x][y] = p[now.first][now.second] + tbl[x][y]; q.push(make_pair(x, y)); } else if (dst[x][y] == dst[now.first][now.second] + 1) { p[x][y] = min(p[x][y], p[now.first][now.second] + tbl[x][y]); } } } if (dst[t.first][t.second] == INF) { return; } SUKASUKA = true; string npath = p[t.first][t.second]; if ((int)npath.size() < (int)path.size() || (int)npath.size() == (int)path.size() && npath < path) { path = npath; } } void gen(int step = 0, int prev = -1) { if (step == K) { solve(); } else { if (prev + 1 == 26) { return; } for (int i = (prev + 1); i < (26); ++i) { got[i] = true; gen(step + 1, i); got[i] = false; } } } void read() { cin >> N >> M >> K; for (int i = (0); i < (N); ++i) for (int j = (0); j < (M); ++j) { cin >> tbl[i][j]; if (tbl[i][j] == 'S') { s.first = i; s.second = j; } if (tbl[i][j] == 'T') { t.first = i; t.second = j; } } } void out() { if (SUKASUKA) { for (int i = (0); i < ((int)path.size() - 1); ++i) { cout << path[i]; } } else { cout << "-1"; } } int main() { read(); gen(); out(); return 0; }
#include <bits/stdc++.h> using namespace std; template <typename T> inline T qmin(const T &a, const T &b) { return a < b ? a : b; } template <typename T> inline T qmax(const T &a, const T &b) { return a > b ? a : b; } template <typename T> inline void getmin(T &a, const T &b) { if (a > b) a = b; } template <typename T> inline void getmax(T &a, const T &b) { if (a < b) a = b; } inline void fileio(string s) { freopen((s + ".in").c_str(), "r", stdin); freopen((s + ".out").c_str(), "w", stdout); } const int inf = 1e9 + 7; const int N = 51, M = 2953; const int go[4][2] = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}}; char g[N][N]; int tp[N][N]; map<int, int> id; int mask[M], cnt; int dis[N][N][M]; bool vis[N][N][M], can[N][N][M]; int ans[N][N][M]; vector<pair<pair<int, int>, int> > to[N][N][M]; int n, m, k, sti, stj, edi, edj; inline void bfs() { static queue<pair<pair<int, int>, int> > q; static int st, ed; dis[sti][stj][1] = 1; q.push(make_pair(make_pair(sti, stj), 1)); while (!q.empty()) { pair<pair<int, int>, int> p = q.front(); q.pop(); int i = p.first.first, j = p.first.second, comb = mask[p.second]; if (dis[i][j][p.second] == dis[edi][edj][1]) break; comb |= (~tp[i][j] ? 1 << tp[i][j] : 0); for (register int d = 0; d < (4); ++d) { int ni = i + go[d][0], nj = j + go[d][1]; if (ni < 1 || ni > n || nj < 1 || nj > m || (ni == sti && nj == stj)) continue; int ncomb = comb; if (~tp[ni][nj]) { ncomb &= ~(1 << tp[ni][nj]); if (__builtin_popcount(ncomb) >= k) continue; } else { ncomb = 0; } int cid = id[ncomb]; if (dis[ni][nj][cid]) { if (dis[ni][nj][cid] == dis[i][j][p.second] + 1) to[i][j][p.second].push_back(make_pair(make_pair(ni, nj), cid)); continue; } dis[ni][nj][cid] = dis[i][j][p.second] + 1; q.push(make_pair(make_pair(ni, nj), cid)); to[i][j][p.second].push_back(make_pair(make_pair(ni, nj), cid)); } } } inline bool cmp(const pair<pair<int, int>, int> &a, const pair<pair<int, int>, int> &b) { pair<int, int> p = a.first, q = b.first; if (g[p.first][p.second] != g[q.first][q.second]) return g[p.first][p.second] < g[q.first][q.second]; if (p.first == edi && p.second == edj) return false; return cmp(to[p.first][p.second][a.second][ans[p.first][p.second][a.second]], to[q.first][q.second][b.second][ans[q.first][q.second][b.second]]); } inline void dfs(int i, int j, int k) { if (vis[i][j][k]) return; vis[i][j][k] = true; if (i == edi && j == edj) { can[i][j][k] = true; return; } int bst = -1; for (register int d = 0; d < (to[i][j][k].size()); ++d) { pair<pair<int, int>, int> p = to[i][j][k][d]; int ni = p.first.first, nj = p.first.second, nk = p.second; dfs(ni, nj, nk); if (can[ni][nj][nk]) { if (bst == -1 || cmp(p, to[i][j][k][bst])) bst = d; } } if (~bst) { ans[i][j][k] = bst; can[i][j][k] = true; } else ans[i][j][k] = -1; } inline void getans(pair<pair<int, int>, int> a) { pair<int, int> p = a.first; if (p.first == edi && p.second == edj) return; if (p.first != sti || p.second != stj) putchar(g[p.first][p.second]); getans(to[p.first][p.second][a.second][ans[p.first][p.second][a.second]]); } int main() { scanf("%d%d%d", &n, &m, &k); for (register int i = (1); i <= (n); ++i) { scanf("%s", g[i] + 1); for (register int j = (1); j <= (m); ++j) { if (g[i][j] == 'S') { tp[i][j] = -1; sti = i, stj = j; } else if (g[i][j] == 'T') { tp[i][j] = -1; edi = i, edj = j; } else { tp[i][j] = g[i][j] - 'a'; } } } id[0] = ++cnt; mask[cnt] = 0; for (register int i = (1); i <= (k - 1); ++i) { for (int comb = (1 << i) - 1, x, y; comb < (1 << 26); x = comb & -comb, y = comb + x, comb = ((comb & ~y) / x >> 1) | y) { id[comb] = ++cnt; mask[cnt] = comb; } } bfs(); if (!dis[edi][edj][1]) return puts("-1"), 0; dfs(sti, stj, 1); getans(make_pair(make_pair(sti, stj), 1)); puts(""); return 0; }
#include <bits/stdc++.h> using namespace std; int n, m, k; char board[3000][3000]; int si, sj, fi, fj; bool found; string ans; bool outside(int x, int y) { return (x < 1 || x > n || y < 1 || y > m); } int bits(int x) { if (x == 0) return 0; return bits(x / 2) + x % 2; } struct node { int x, y, mask; string way; bool operator<(const node &other) const { if (way.length() != other.way.length()) return way.length() > other.way.length(); return way > other.way; } }; int sx, sy; set<int> done[55][55]; priority_queue<node> qu; vector<int> dx, dy; int smask[55][55]; int main() { ios_base::sync_with_stdio(0); dx.push_back(0); dx.push_back(0); dx.push_back(1); dx.push_back(-1); dy.push_back(-1); dy.push_back(1); dy.push_back(0); dy.push_back(0); cin >> n >> m >> k; for (int i = 1; i <= n; i++) { string st; cin >> st; for (int j = 1; j <= m; j++) { board[i][j] = st[j - 1]; if (board[i][j] == 'S') { si = i; sj = j; } if (board[i][j] == 'T') { fi = i; fj = j; } } } node temp; temp.x = si; temp.y = sj; temp.mask = 0; temp.way = ""; qu.push(temp); found = 0; while (qu.size()) { node cur = qu.top(); qu.pop(); int qx = cur.x; int qy = cur.y; if (found) break; for (int dir = 0; dir < 4; dir++) { int nx = qx + dx[dir]; int ny = qy + dy[dir]; if (outside(nx, ny)) continue; if (board[nx][ny] == 'S') continue; if (board[nx][ny] == 'T' && found == 0) { found = 1; ans = cur.way; break; } int nmask = (cur.mask | (1 << (board[nx][ny] - 'a'))); if (bits(nmask) > k) continue; if (done[nx][ny].find(nmask) != done[nx][ny].end()) continue; if ((smask[nx][ny] & nmask) == smask[nx][ny] && smask[nx][ny] > 0) continue; smask[nx][ny] = nmask; done[nx][ny].insert(nmask); temp.x = nx; temp.y = ny; temp.mask = nmask; temp.way = cur.way + board[nx][ny]; qu.push(temp); } } if (found == 0) cout << -1 << endl; else cout << ans << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int MAXN = 61; const int MAXA = 31; const int INF = 1000000000; const int MAXM = 10010; const int w[4][2] = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}}; struct P { P() {} P(int xx, int yy) : x(xx), y(yy) {} bool operator==(const P &p) const { return x == p.x && y == p.y; } int x, y; } start, target; char mp[MAXN][MAXN]; int ch[MAXA]; bool vis[MAXA]; int dist[MAXN][MAXN]; int ctot; int n, m, k; int ans; char path[MAXM], curpath[MAXM]; void init() { scanf("%d%d%d", &n, &m, &k); for (int i = 0; i < n; ++i) scanf("%s", mp[i]); ctot = 0; memset(vis, 0, sizeof(vis)); for (int i = 0; i < n; ++i) for (int j = 0; j < m; ++j) if (mp[i][j] == 'S') start = P(i, j); else if (mp[i][j] == 'T') target = P(i, j); else { if (!vis[mp[i][j] - 'a']) { ch[ctot++] = mp[i][j] - 'a'; vis[mp[i][j] - 'a'] = 1; } } k = min(ctot, k); } P que[MAXM]; void bfs() { for (int i = 0; i < n; ++i) for (int j = 0; j < m; ++j) dist[i][j] = -1; que[0] = target; dist[target.x][target.y] = 0; P p; for (int k1 = 0, k2 = 1, k3 = 1, step = 1; k1 < k2; k1 = k3, k3 = k2, ++step) for (int i = k1; i < k3; ++i) for (int l = 0; l < 4; ++l) { p.x = que[i].x + w[l][0]; p.y = que[i].y + w[l][1]; if (!(0 <= (p.x) && (p.x) < n && 0 <= (p.y) && (p.y) < m) || dist[p.x][p.y] != -1 || (mp[p.x][p.y] != 'S' && !vis[mp[p.x][p.y] - 'a'])) continue; dist[p.x][p.y] = step; que[k2++] = p; } if (dist[start.x][start.y] == -1 || dist[start.x][start.y] > ans) return; que[0] = start; int len = 0; for (int k1 = 0, k2 = 1, k3 = 1, step = dist[start.x][start.y] - 1; k1 < k2; k1 = k3, k3 = k2, --step) { char c = 127; for (int i = k1; i < k3; ++i) for (int l = 0; l < 4; ++l) { p.x = que[i].x + w[l][0]; p.y = que[i].y + w[l][1]; if (!(0 <= (p.x) && (p.x) < n && 0 <= (p.y) && (p.y) < m) || dist[p.x][p.y] != step) continue; c = min(c, mp[p.x][p.y]); } if (c == 'T') break; curpath[len++] = c; for (int i = k1; i < k3; ++i) for (int l = 0; l < 4; ++l) { p.x = que[i].x + w[l][0]; p.y = que[i].y + w[l][1]; if (!(0 <= (p.x) && (p.x) < n && 0 <= (p.y) && (p.y) < m) || dist[p.x][p.y] != step || mp[p.x][p.y] != c) continue; dist[p.x][p.y] = -1; que[k2++] = p; } } curpath[len] = '\0'; if (ans > dist[start.x][start.y] || strcmp(curpath, path) < 0) { ans = dist[start.x][start.y]; strcpy(path, curpath); } } void cal(int step, int pt) { if (step == 0) { bfs(); return; } for (int i = pt; i <= ctot - step; ++i) { vis[ch[i]] = 1; cal(step - 1, i + 1); vis[ch[i]] = 0; } } void solve() { memset(vis, 0, sizeof(vis)); ans = INF; path[0] = 127; path[1] = '\0'; cal(k, 0); if (ans == INF) puts("-1"); else printf("%s\n", path); } int main() { init(); solve(); return 0; }
#include <bits/stdc++.h> using namespace std; const int mr[] = {0, 1, 0, -1}; const int mc[] = {1, 0, -1, 0}; int sr, sc, tr, tc; int dp[52][52]; char a[52][52]; string gao(int x, int n, const string& s) { if (n) { string ret = "-1"; for (int i = x; i < 26; i++) { string tmp = gao(i + 1, n - 1, s + char(i + 'a')); if (tmp == "-1") continue; if (ret == "-1" || tmp.size() < ret.size() || tmp.size() == ret.size() && tmp < ret) ret = tmp; } return ret; } vector<pair<int, int>> u = {{tr, tc}}, v; memset(dp, 255, sizeof(dp)); dp[tr][tc] = 4; while (!u.empty()) { v.clear(); for (auto c : s) for (auto r : u) { int fr = r.first; int fc = r.second; if (fr == sr && fc == sc) { string ret; while (1) { int o = dp[fr][fc]; fr += mr[o]; fc += mc[o]; if (fr == tr && fc == tc) break; ret += a[fr][fc]; } return ret; } for (int o = 0; o < 4; o++) { int dr = fr + mr[o]; int dc = fc + mc[o]; if (a[dr][dc] != c || ~dp[dr][dc]) continue; dp[dr][dc] = (o + 2) % 4; v.push_back({dr, dc}); } } v.swap(u); } return "-1"; } int main() { int n, m, k; scanf("%d%d%d", &n, &m, &k); for (int i = 1; i <= n; i++) { scanf("%s", a[i] + 1); for (int j = 1; j <= m; j++) { if (a[i][j] == 'S') a[sr = i][sc = j] = '.'; if (a[i][j] == 'T') a[tr = i][tc = j] = '.'; } } puts(gao(0, k, ".").c_str()); }
#include <bits/stdc++.h> using namespace std; int dx[4] = {1, -1, 0, 0}; int dy[4] = {0, 0, -1, 1}; int n, m, k, sx, sy, fx, fy; string s[60], a[60][60], res; vector<int> qx, qy; bool ok[26]; bool valid(int x, int y) { if (x >= 0 && y >= 0 && x < n && y < m) return 1; return 0; } void bfs() { for (int i = 0; i < qx.size(); i++) { int x, y; for (int j = 0; j < 4; j++) { x = qx[i] + dx[j]; y = qy[i] + dy[j]; if (valid(x, y) && (s[x][y] == 'T' || s[x][y] == 'S' || ok[s[x][y] - 'a'])) { if (a[x][y].size() == 0) { qx.push_back(x); qy.push_back(y); a[x][y] = a[qx[i]][qy[i]] + s[x][y]; } else if ((a[x][y].size() > a[qx[i]][qy[i]].size() + 1) || (a[x][y].size() == a[qx[i]][qy[i]].size() + 1 && a[x][y] > a[qx[i]][qy[i]] + s[x][y])) { a[x][y] = a[qx[i]][qy[i]] + s[x][y]; } } } } } void f(int x, int y) { if (x == 0) { for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) a[i][j].clear(); qx.clear(); qy.clear(); qx.push_back(sx); qy.push_back(sy); bfs(); if (a[fx][fy].size()) { if (!res.size() || res.size() > a[fx][fy].size() || (a[fx][fy].size() == res.size() && res > a[fx][fy])) { res = a[fx][fy]; } } } else { for (int i = y; i < 26; i++) { ok[i] = 1; f(x - 1, i + 1); ok[i] = 0; } } } int main() { cin >> n >> m >> k; for (int i = 0; i < n; i++) cin >> s[i]; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { if (s[i][j] == 'S') { sx = i; sy = j; } if (s[i][j] == 'T') { fx = i; fy = j; } } f(k, 0); if (res.size()) { for (int i = 0; i < res.size() - 1; i++) cout << res[i]; cout << endl; } else cout << -1 << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 55; char ssG[N][N]; int R, C, KK; int stx, sty, enx, eny; struct nodexx { string str; int x, y, val; bool operator<(const nodexx t) const { int lenaa = str.size(), lenbb = t.str.size(); if (lenaa - lenbb) return lenaa > lenbb; return str > t.str; } } XA, XB; priority_queue<nodexx> QQ; set<pair<pair<int, int>, int> > SET; int dirc[4][2] = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}}; int has[55][55]; bool Judge(int x) { int cnt = 0; while (x > 0) { cnt += x % 2; x /= 2; } return cnt <= KK; } string BFS() { memset(has, 0, sizeof has); SET.clear(); while (QQ.size()) QQ.pop(); XA.str = "", XA.x = stx, XA.y = sty, XA.val = 0, QQ.push(XA); SET.insert(make_pair(make_pair(stx, sty), 0)); int k, r, c, val; while (QQ.size()) { XA = QQ.top(), QQ.pop(); for (k = 0; k < 4; k++) { r = XA.x + dirc[k][0], c = XA.y + dirc[k][1]; if (r >= 0 && r < R && c >= 0 && c < C && ssG[r][c] != 'S') { if (ssG[r][c] == 'T') return XA.str; val = XA.val | (1 << (ssG[r][c] - 'a')); if (Judge(val) && SET.count(make_pair(make_pair(r, c), val)) == 0) { if (has[r][c] && (has[r][c] & val) == has[r][c]) continue; has[r][c] = val; SET.insert(make_pair(make_pair(r, c), val)); XB.str = XA.str + ssG[r][c]; XB.val = val; XB.x = r; XB.y = c; QQ.push(XB); } } } } return "-1"; } void cyh() { cout << BFS() << endl; } int main() { int e, f; while (cin >> R >> C >> KK) { for (e = 0; e < R; e++) { scanf("%s", ssG[e]); for (f = 0; f < C; f++) { if (ssG[e][f] == 'S') stx = e, sty = f; if (ssG[e][f] == 'T') enx = e, eny = f; } } cyh(); } return 0; }
#include <bits/stdc++.h> using namespace std; struct triple { int val, r, c, par; triple(int _v, int _r, int _c, int _p) { val = _v, r = _r, c = _c, par = _p; } bool operator<(const triple &a) const { return val > a.val; } }; int n, m, k, len; int rs, cs, re, ce; int dir[4][2] = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}}; char mat[60][60]; bool mark[60][60]; int dist[60][60]; int par[60][60]; bool ok[30]; string res; priority_queue<triple> q[2]; string bfs() { for (int i = 0; i < 2; i++) while (!q[i].empty()) q[i].pop(); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { mark[i][j] = false; dist[i][j] = -1; par[i][j] = -1; } } dist[rs][cs] = 0; int cur = 0, bef = 1, prev, cnt; q[cur].push(triple(1, rs, cs, -1)); while (!q[0].empty() || !q[1].empty()) { if (q[bef].empty()) { bef = 1 - bef; cur = 1 - cur; prev = cnt = 0; } triple t = q[bef].top(); q[bef].pop(); int r = t.r; int c = t.c; int val = t.val; if (val > prev) cnt++; prev = val; if (par[r][c] != -1) continue; par[r][c] = t.par; if (r == re && c == ce) break; for (int i = 0; i < 4; i++) { int nr = r + dir[i][0]; int nc = c + dir[i][1]; if ((nr == re && nc == ce) || (nr >= 0 && nr < n && nc >= 0 && nc < m && ok[mat[nr][nc] - 'a'])) { if (dist[nr][nc] == -1 || dist[nr][nc] == dist[r][c] + 1) { dist[nr][nc] = dist[r][c] + 1; int nval = cnt * 30 + mat[nr][nc] - 'a'; q[cur].push(triple(nval, nr, nc, i)); } } } } if (par[re][ce] == -1) return ""; string res; int x = re, y = ce; while (x != rs || y != cs) { res = mat[x][y] + res; int p = par[x][y]; x -= dir[p][0]; y -= dir[p][1]; } return res; } void bt(int str, int rem) { if (rem == 0) { string tmp = bfs(); if (tmp.length() < 1) return; tmp = tmp.substr(0, (int)tmp.length() - 1); if (len == -1 || tmp.length() < len || (tmp.length() == len && tmp < res)) { len = tmp.length(); res = tmp; } } else { for (int i = str; i < 26; i++) { ok[i] = true; bt(i + 1, rem - 1); ok[i] = false; } } } int main() { while (cin >> n >> m >> k) { len = -1; res = ""; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { cin >> mat[i][j]; if (mat[i][j] == 'S') rs = i, cs = j; if (mat[i][j] == 'T') re = i, ce = j; } } bt(0, k); if (len == -1) cout << -1 << endl; else cout << res << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; struct Node { int r, c; }; struct Node2 { int r, c, pr, pc; }; int N, M, K, SR, SC, TR, TC; char grid[52][52], cost2[50 * 50 + 2]; int cost[52][52], SP, mini; bool vis[52][52], available[512]; int dr[] = {-1, 1, 0, 0}, dc[] = {0, 0, 1, -1}; Node parent[52][52]; string ans; bool operator<(const Node2 &a, const Node2 &b) { if (cost[a.r][a.c] != cost[b.r][b.c]) return cost[a.r][a.c] > cost[b.r][b.c]; if (grid[a.r][a.c] != grid[b.r][b.c]) return grid[a.r][a.c] < grid[b.r][b.c]; if (a.r != b.r) return a.r < b.r; if (a.c != b.c) return a.c < b.c; if (a.pr != b.pr) return a.pr < b.pr; return a.pc < b.pc; } void getCoordinates(int &R, int &C, char x, char y) { for (int i = 0; i < N; i++) for (int j = 0; j < M; j++) if (grid[i][j] == x) R = i, C = j, grid[i][j] = y; } void bfs() { SP = 1 << 30; memset(vis, 0, sizeof vis); memset(cost, 63, sizeof cost); queue<Node> q; q.push(Node{TR, TC}); cost[TR][TC] = 0; while (!q.empty()) { Node cur = q.front(), t; q.pop(); if (cur.r == SR && cur.c == SC) { SP = cost[SR][SC]; return; } if (vis[cur.r][cur.c]) continue; vis[cur.r][cur.c] = true; for (int i = 0; i < 4; i++) { t = Node{cur.r + dr[i], cur.c + dc[i]}; if (t.r >= 0 && t.r < N && t.c >= 0 && t.c < M && !vis[t.r][t.c] && available[(int)grid[t.r][t.c]] && cost[t.r][t.c] > cost[cur.r][cur.c] + 1) { cost[t.r][t.c] = cost[cur.r][cur.c] + 1; q.push(t); } } } } void dijkstra() { for (int i = 0; i < N; i++) for (int j = 0; j < M; j++) parent[i][j] = Node{-1, -1}; if (cost[SR][SC] >= 1 << 20) return; memset(vis, 0, sizeof vis); memset(cost2, 'z' + 5, sizeof cost2); set<Node2> s; s.insert(Node2{SR, SC, -1, -1}); while (!s.empty()) { Node2 cur = *s.begin(); s.erase(s.begin()); if (vis[cur.r][cur.c] || cost2[SP - cost[cur.r][cur.c]] < grid[cur.r][cur.c]) continue; vis[cur.r][cur.c] = true; cost2[SP - cost[cur.r][cur.c]] = grid[cur.r][cur.c]; parent[cur.r][cur.c] = Node{cur.pr, cur.pc}; if (cur.r == TR && cur.c == TC) return; for (int i = 0; i < 4; i++) { Node2 t = Node2{cur.r + dr[i], cur.c + dc[i], cur.r, cur.c}; if (t.r >= 0 && t.r < N && t.c >= 0 && t.c < M && cost[t.r][t.c] + 1 == cost[cur.r][cur.c]) s.insert(t); } } } string getPath() { Node cur{TR, TC}; string ret = ""; while (cur.r != -1) { ret += grid[cur.r][cur.c]; cur = parent[cur.r][cur.c]; } ret = ret.substr(1, (int)ret.size() - 2); reverse(ret.begin(), ret.end()); return ret; } void choose(int k, char from) { if (k == K) { bfs(); dijkstra(); string best = getPath(); if (SP < mini || (SP == mini && best < ans)) mini = SP, ans = best; return; } for (char i = from; i <= 'z'; i++) { available[(int)i] = true; choose(k + 1, i + 1); available[(int)i] = false; } } int main() { for (int i = 0; i < N; i++) for (int j = 0; j < M; j++) parent[i][j] = Node{-1, -1}; scanf("%d %d %d", &N, &M, &K); for (int i = 0; i < N; i++) scanf("%s", grid[i]); getCoordinates(SR, SC, 'S', 'a' - 1); getCoordinates(TR, TC, 'T', 'z' + 1); available['a' - 1] = available['z' + 1] = true; mini = 1 << 30; choose(0, 'a'); if (mini == 1 << 30) printf("-1\n"); else printf("%s\n", ans.c_str()); }
#include <bits/stdc++.h> using namespace std; const int dy[] = {-1, 0, 1, 0}, dx[] = {0, -1, 0, 1}; inline int D(int x1, int y1, int x2, int y2) { return abs(x1 - x2) + abs(y1 - y2); } int h, w, k; string in[50]; void run() { cin >> h >> w >> k; int sy, sx, gy, gx; for (int i = 0; i < h; i++) { cin >> in[i]; for (int j = 0; j < w; j++) { if (in[i][j] == 'S') sy = i, sx = j; else if (in[i][j] == 'T') gy = i, gx = j; } } set<pair<int, int> > s; priority_queue<pair<int, pair<pair<string, int>, int> >, vector<pair<int, pair<pair<string, int>, int> > >, greater<pair<int, pair<pair<string, int>, int> > > > q; q.push( make_pair(D(sy, sx, gy, gx), make_pair(make_pair("", 0), sy * w + sx))); while (!q.empty()) { int y = q.top().second.second / w, x = q.top().second.second % w; string str = q.top().second.first.first; int mask = q.top().second.first.second; q.pop(); if (s.count(make_pair(mask, y * w + x))) continue; s.insert(make_pair(mask, y * w + x)); for (int d = 0; d < 4; d++) { int ny = y + dy[d], nx = x + dx[d]; if (ny < 0 || nx < 0 || ny >= h || nx >= w || ny == sy && nx == sx) continue; if (ny == gy && nx == gx) { cout << str << endl; return; } string next = str + in[ny][nx]; int nmask = mask | 1 << in[ny][nx] - 'a'; if (__builtin_popcount(nmask) <= k) q.push(make_pair(D(ny, nx, gy, gx) + next.size(), make_pair(make_pair(next, nmask), ny * w + nx))); } } cout << -1 << endl; } int main() { run(); return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = 1000000000; const long long LINF = 1000000000000000000LL; void prepare() {} int n, m, k; char x[55][55]; pair<int, int> start, finish; int rev[255]; char rev2[10]; struct mystring { vector<int> a; int sz; mystring() { sz = 10; } void push_back(char x) { if (x == 'T') return; if (sz == 10) { a.push_back(rev[x] << 27); sz = 1; } else { sz++; a[a.size() - 1] |= (rev[x] << (3 * (10 - sz))); } } string get(int q, int sz) { string ret = ""; ret.resize(sz); for (int i = 0; i < sz; i++) { ret[i] = rev2[(q >> (3 * (9 - i))) & 7]; } return ret; } string c_str() { if (a.size() == 0) return ""; string ret = ""; for (int i = 0; i < a.size() - 1; i++) ret += get(a[i], 10); return ret + get(a[a.size() - 1], sz); } }; bool operator<(const mystring &a, const mystring &b) { for (int i = 0; i < a.a.size(); i++) if (a.a[i] != b.a[i]) return a.a[i] < b.a[i]; return false; } bool operator>(const mystring &a, const mystring &b) { for (int i = 0; i < a.a.size(); i++) if (a.a[i] != b.a[i]) return a.a[i] > b.a[i]; return false; } bool ok[256]; int dx[4] = {-1, 0, 1, 0}; int dy[4] = {0, -1, 0, 1}; queue<pair<int, int> > dq; int dp[55][55]; pair<int, int> last[55][55]; string rew[55][55]; string getans() { int sz = dp[finish.first][finish.second]; if (sz == INF) return ""; pair<int, int> cur = finish; string ret = ""; for (int i = 0; i < sz - 1; i++) { cur = last[cur.first][cur.second]; ret += x[cur.first][cur.second]; } reverse(ret.begin(), ret.end()); return ret; } inline string rewind(pair<int, int> z) { string ret = ""; int gg = dp[z.first][z.second], i = 0; ret.resize(gg + 1); while (z.first != -1) { ret[gg - i] = x[z.first][z.second]; z = last[z.first][z.second]; i++; } return ret; } bool dij() { for (int i = 0; i < 55; i++) for (int j = 0; j < 55; j++) { dp[i][j] = INF; rew[i][j] = ""; } dp[start.first][start.second] = 0; dq.push(start); while (!dq.empty()) { pair<int, int> cur = dq.front(); dq.pop(); string r = rew[cur.first][cur.second]; if (cur != start) r.push_back(x[cur.first][cur.second]); for (int k = 0; k < 4; k++) { int nr = cur.first + dy[k]; int nc = cur.second + dx[k]; if (nr >= 0 && nr < n && nc >= 0 && nc < m) if (ok[x[nr][nc]]) { int nval = dp[cur.first][cur.second] + 1; if (dp[nr][nc] > nval) { dp[nr][nc] = nval; rew[nr][nc] = r; dq.push(make_pair(nr, nc)); } else if (dp[nr][nc] == nval) { if (rew[nr][nc] > r) rew[nr][nc] = r; } } } } return dp[finish.first][finish.second] != INF; } pair<int, string> ans; bool use[256]; int qq; void go(int it, char last) { if (it == 0) { if (dij()) { pair<int, string> tmp = make_pair(dp[finish.first][finish.second], rew[finish.first][finish.second]); if (ans > tmp) ans = tmp; } return; } for (char x = last; x <= 'z'; x++) if (use[x]) { ok[x] = true; rev[x] = 5 - it; rev2[5 - it] = x; go(it - 1, x + 1); ok[x] = false; } } bool solve() { memset(use, 0, sizeof(use)); scanf("%d%d%d", &n, &m, &k); for (int i = 0; i < n; i++) { scanf("%s", x[i]); for (int j = 0; j < m; j++) { use[x[i][j]] = true; if (x[i][j] == 'S') start = make_pair(i, j); else if (x[i][j] == 'T') finish = make_pair(i, j); } } memset(ok, 0, sizeof(ok)); ok['S'] = true; ok['T'] = true; int sk = 0; for (char a = 'a'; a <= 'z'; a++) if (use[a]) sk++; k = min(k, sk); ans = make_pair(INF, "Z"); go(k, 'a'); if (ans.first == INF) printf("-1\n"); else { for (int i = 0; i < ans.second.size(); i++) printf("%c", ans.second[i]); printf("\n"); } return false; } int main() { prepare(); while (solve()) ; return 0; }
#include <bits/stdc++.h> using namespace std; struct point { char h; string res; bool poss; }; point a[50][50]; int n, m, k; string res; vector<int> qx, qy; int step[4][2] = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}}; void bfs() { for (int i = 0; i < qx.size(); i++) { int x, y; for (int j = 0; j < 4; j++) { x = qx[i] + step[j][0]; y = qy[i] + step[j][1]; if (x > -1 && y > -1 && x < n && y < m && a[x][y].poss) { if (a[x][y].res.size() == 0) { qx.push_back(x); qy.push_back(y); a[x][y].res = a[qx[i]][qy[i]].res + a[x][y].h; } else { if (a[x][y].res.size() == a[qx[i]][qy[i]].res.size() + 1 && a[x][y].res > a[qx[i]][qy[i]].res + a[x][y].h) { a[x][y].res = a[qx[i]][qy[i]].res + a[x][y].h; } } } } } } vector<char> temp, meeted; char now[6]; int startx, starty, fx, fy; void pere(int deep, int start) { for (int i = start; i < meeted.size(); i++) { now[deep + 2] = meeted[i]; if (deep == k - 1) { qx.clear(); qy.clear(); qx.push_back(startx); qy.push_back(starty); for (int ii = 0; ii < n; ii++) for (int jj = 0; jj < m; jj++) { a[ii][jj].res.clear(); a[ii][jj].poss = false; for (int j = 0; j < k + 2; j++) if (a[ii][jj].h == now[j]) a[ii][jj].poss = true; } a[startx][starty].res = "S"; bfs(); if (a[fx][fy].res.size()) { if (!res.size() || res.size() > a[fx][fy].res.size() || (a[fx][fy].res.size() == res.size() && res > a[fx][fy].res)) res = a[fx][fy].res; } } else { pere(deep + 1, i + 1); } } } int main() { cin >> n >> m >> k; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { cin >> a[i][j].h; if (a[i][j].h == 'S') { startx = i; starty = j; } if (a[i][j].h == 'T') { fx = i; fy = j; } if (a[i][j].h >= 'a') temp.push_back(a[i][j].h); } } now[0] = 'S'; now[1] = 'T'; sort(temp.begin(), temp.end()); for (int i = 0; i < temp.size(); i++) { if (!i || temp[i] != temp[i - 1]) meeted.push_back(temp[i]); } k = min(k, int(meeted.size())); if (meeted.size() == 0) return 0; pere(0, 0); if (res.size() == 0) cout << -1; else { for (int i = 1; i < res.size() - 1; i++) cout << res[i]; } }
#include <bits/stdc++.h> using namespace std; const long long MOD = 1e9 + 7; const int INF = 2e9; const long long INF64 = 9e18; const long double EPS = 1e-12; const long double PI = 3.1415926535897932384626433832795028841; const long long MD = 925262732; const long long T = 634521; const int N = 200010; const int M = 201; int n, m, k, c[5], mini = INF, d[51][51]; bool mark[51][51]; string ans, a[M]; pair<int, int> s, f; queue<pair<int, int> > q; vector<pair<int, int> > qq[3]; bool get(int first, int second) { if (!(first >= 0 && second >= 0 && first < n && second < m)) return 0; bool f = 0; for (int i = 0; i < int(k); i++) if (a[first][second] == c[i]) f = 1; if (a[first][second] == 'S') f = 1; return f; } void bfs() { for (int i = 0; i < int(n); i++) for (int j = 0; j < int(m); j++) { d[i][j] = INF; mark[i][j] = 0; } d[f.first][f.second] = 0; q.push(f); while (!q.empty()) { pair<int, int> v = q.front(); q.pop(); for (int i = -1; i <= 1; i++) for (int j = -1; j <= 1; j++) if (abs(i) + abs(j) == 1) if (get(v.first + i, v.second + j) && d[v.first + i][v.second + j] > d[v.first][v.second] + 1) { q.push(make_pair(v.first + i, v.second + j)); d[v.first + i][v.second + j] = d[v.first][v.second] + 1; } } int sum = d[s.first][s.second]; int ss = sum; if (sum == INF) return; if (sum == 1) exit(0); string s1 = ""; int first = s.first, second = s.second; qq[0].clear(); qq[1].clear(); qq[sum % 2].push_back(s); while (sum > 1) { int c = 'z'; int t = sum % 2, tt = (sum - 1) % 2; qq[tt].clear(); for (int u = 0; u < int(int((qq[t]).size())); u++) for (int i = -1; i <= 1; i++) for (int j = -1; j <= 1; j++) if (abs(i) + abs(j) == 1) { int xx = qq[t][u].first + i, yy = qq[t][u].second + j; if (get(xx, yy) && d[xx][yy] == sum - 1 && a[xx][yy] <= c) c = a[xx][yy]; } for (int u = 0; u < int(int((qq[t]).size())); u++) for (int i = -1; i <= 1; i++) for (int j = -1; j <= 1; j++) if (abs(i) + abs(j) == 1) { int xx = qq[t][u].first + i, yy = qq[t][u].second + j; if (get(xx, yy) && d[xx][yy] == sum - 1 && a[xx][yy] == c && !mark[xx][yy]) { qq[tt].push_back(make_pair(xx, yy)); mark[xx][yy] = 1; } } if (c != 'S') s1 = s1 + (char)c; sum--; } if (ss < mini) { mini = ss; ans = s1; } else if (ss == mini) ans = min(ans, s1); } int main() { cin >> n >> m >> k; for (int i = 0; i < int(n); i++) { cin >> a[i]; for (int j = 0; j < int(m); j++) if (a[i][j] == 'S') s = make_pair(i, j); else if (a[i][j] == 'T') f = make_pair(i, j); } for (c[0] = 'a'; c[0] <= 'z'; c[0]++) for (c[1] = c[0]; c[1] <= 'z'; c[1]++) for (c[2] = c[1]; c[2] <= 'z'; c[2]++) for (c[3] = c[2]; c[3] <= 'z'; c[3]++) bfs(); if (mini == INF) cout << -1; else cout << ans; return 0; }
#include <bits/stdc++.h> using namespace std; const int dx[4] = {-1, 0, 1, 0}, dy[4] = {0, 1, 0, -1}; struct state { int x, y, h; string s; state(int a, int b, int c, string d) : x(a), y(b), h(c), s(d) {} bool operator<(const state &b) const { return b.s.size() != s.size() ? s.size() > b.s.size() : s > b.s; } }; char a[55][55]; int n, m, lim, last[55][55]; set<int> s[55][55]; int main() { cin >> n >> m >> lim; for (int i = 0; i < n; i++) cin >> a[i]; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) if (a[i][j] == 'S') { priority_queue<state> q; q.push({i, j, 0, ""}); while (!q.empty()) { auto cur = q.top(); q.pop(); for (int d = 0; d < 4; d++) { int x = cur.x + dx[d], y = cur.y + dy[d]; if (x < 0 || y < 0 || x >= n || y >= m) continue; if (a[x][y] == 'T') { cout << cur.s << '\n'; exit(0); } if (a[x][y] == 'S') continue; int h = cur.h | (1 << (a[x][y] - 'a')); if (__builtin_popcount(h) > lim || s[x][y].count(h)) continue; if (last[x][y] && (last[x][y] & h) == last[x][y]) continue; last[x][y] = h; s[x][y].insert(h); q.push({x, y, h, cur.s + a[x][y]}); } } puts("-1"); exit(0); } }
#include <bits/stdc++.h> using namespace std; int n, m, k; int sx, sy, tx, ty; char a[60][60]; bool ok[26]; int dis[60][60]; int d[4][2] = {0, 1, 1, 0, 0, -1, -1, 0}; int val[60][60]; pair<int, int> lst[60][60]; vector<pair<int, int> > tot[110]; vector<int> fst[26]; vector<int> snd[2510]; string ans; bool good; void solve() { for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) dis[i][j] = -1; dis[sx][sy] = 0; queue<pair<int, int> > q; q.push(make_pair(sx, sy)); while (!q.empty()) { int x = q.front().first, y = q.front().second; q.pop(); for (int i = 0; i < 4; i++) { int xx = x + d[i][0], yy = y + d[i][1]; if (xx < 1 || xx > n || yy < 1 || yy > m) continue; if (dis[xx][yy] != -1 || (a[xx][yy] != 'T' && !ok[a[xx][yy] - 'a'])) continue; dis[xx][yy] = dis[x][y] + 1; q.push(make_pair(xx, yy)); } } if (dis[tx][ty] == -1) return; for (int i = 1; i <= dis[tx][ty]; i++) tot[i].clear(); for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { if (dis[i][j] <= 0 || dis[i][j] > dis[tx][ty]) continue; tot[dis[i][j]].push_back(make_pair(i, j)); } } val[sx][sy] = 1; int sz = 1; for (int i = 1; i <= dis[tx][ty]; i++) { for (int j = 0; j < 26; j++) fst[j].clear(); for (int j = 1; j <= sz; j++) snd[j].clear(); for (int j = 0; j < (int)tot[i].size(); j++) { int x = tot[i][j].first, y = tot[i][j].second; if (a[x][y] != 'T') fst[a[x][y] - 'a'].push_back(j); val[x][y] = 1e9; for (int t = 0; t < 4; t++) { int xx = x + d[t][0], yy = y + d[t][1]; if (xx < 1 || xx > n || yy < 1 || yy > m) continue; if (dis[xx][yy] != dis[x][y] - 1) continue; if (val[xx][yy] < val[x][y]) val[x][y] = val[xx][yy], lst[x][y] = make_pair(xx, yy); } } for (int j = 0; j < 26; j++) { for (int t = 0; t < (int)fst[j].size(); t++) { int x = tot[i][fst[j][t]].first, y = tot[i][fst[j][t]].second; snd[val[x][y]].push_back(fst[j][t]); } } int tsz = 0; int lx = 0, ly = 0, lv = 0; for (int j = 1; j <= sz; j++) { for (int t = 0; t < (int)snd[j].size(); t++) { int x = tot[i][snd[j][t]].first, y = tot[i][snd[j][t]].second; if (lx && ly && lv == val[x][y] && a[lx][ly] == a[x][y]) lv = val[x][y], val[x][y] = tsz; else lv = val[x][y], val[x][y] = ++tsz; lx = x; ly = y; } } sz = tsz; } string res = ""; int x = lst[tx][ty].first, y = lst[tx][ty].second; while (x != sx || y != sy) { res = a[x][y] + res; int ttx = lst[x][y].first, tty = lst[x][y].second; x = ttx; y = tty; } if (!good || (int)res.size() < (int)ans.size() || ((int)res.size() == (int)ans.size() && res < ans)) ans = res; good = true; } void dfs(int x, int lst) { if (x > k) { solve(); return; } for (int i = lst; i < 26; i++) { ok[i] = true; dfs(x + 1, i + 1); ok[i] = false; } } int main() { scanf("%d%d%d", &n, &m, &k); for (int i = 1; i <= n; i++) { scanf("%s", a[i] + 1); for (int j = 1; j <= m; j++) { if (a[i][j] == 'S') sx = i, sy = j; if (a[i][j] == 'T') tx = i, ty = j; } } dfs(1, 0); if (!good) printf("-1"); else cout << ans; return 0; }
#include <bits/stdc++.h> using namespace std; template <class T> T abs(T x) { return x > 0 ? x : (-x); } template <class T> T sqr(T x) { return x * x; } const int maxn = 57; char ty[maxn][maxn]; bool allow[300]; int d[maxn][maxn]; int f[maxn][maxn]; int n, m, k; int sx, sy, fx, fy; int Q[maxn * maxn * 2]; int qs, qt; const int dx[] = {-1, 0, 0, 1}; const int dy[] = {0, -1, 1, 0}; void bfs() { d[sx][sy] = 0; qs = 0, qt = 0; Q[qs++] = sx * maxn + sy; while (qs > qt) { int x = Q[qt] / maxn; int y = Q[qt] % maxn; if (x == fx && y == fy) break; ++qt; for (int dir = 0; dir < 4; ++dir) { int X = x + dx[dir], Y = y + dy[dir]; if (X < 0 || Y < 0 || X >= n || Y >= m) continue; if (d[X][Y] != -1) continue; if (!allow[ty[X][Y]]) continue; d[X][Y] = d[x][y] + 1; f[X][Y] = x * maxn + y; Q[qs++] = X * maxn + Y; } } } string cur; string rf[maxn][maxn]; bool uf[maxn][maxn]; void rest() { memset(uf, 0, sizeof(uf)); rf[sx][sy] = "S"; qs = 0, qt = 0; uf[sx][sy] = true; Q[qs++] = sx * maxn + sy; while (qs > qt) { int x = Q[qt] / maxn; int y = Q[qt] % maxn; if (x == fx && y == fy) break; ++qt; string& s = rf[x][y]; for (int dir = 0; dir < 4; ++dir) { int X = x + dx[dir], Y = y + dy[dir]; if (X < 0 || Y < 0 || X >= n || Y >= m) continue; if (d[X][Y] != d[x][y] + 1) continue; if (!uf[X][Y]) { uf[X][Y] = true; rf[X][Y] = rf[x][y] + ty[X][Y]; Q[qs++] = X * maxn + Y; } else { rf[X][Y] = min(rf[X][Y], rf[x][y] + ty[X][Y]); } } } cur = rf[fx][fy]; } int main() { cin >> n >> m >> k; for (int i = 0; i < n; ++i) { string s; cin >> s; for (int j = 0; j < m; ++j) { ty[i][j] = s[j]; if (islower(s[j])) { continue; } if (s[j] == 'S') sx = i, sy = j; else fx = i, fy = j; } } int res = 100500100; string rs; bool rsf = false; set<long long> S; for (int i = 'a'; i <= 'z'; ++i) for (int j = 'a'; j <= i; ++j) for (int p = 'a'; p <= j; ++p) for (int q = 'a'; q <= p; ++q) { long long h = 123; if (k >= 1) h = h * 2184057 + i; if (k >= 2) h = h * 2184057 + j; if (k >= 3) h = h * 2184057 + p; if (k >= 4) h = h * 2184057 + q; if (S.count(h)) continue; S.insert(h); memset(allow, 0, sizeof(allow)); if (k >= 1) allow[i] = true; if (k >= 2) allow[j] = true; if (k >= 3) allow[p] = true; if (k >= 4) allow[q] = true; allow['S'] = allow['T'] = true; memset(d, -1, sizeof(d)); bfs(); if (d[fx][fy] == -1) continue; if (d[fx][fy] > res) continue; if (res > d[fx][fy]) res = d[fx][fy]; } S.clear(); int bad = 1000000; for (int i = 'a'; i <= 'z'; ++i) for (int j = 'a'; j <= i; ++j) for (int p = 'a'; p <= j; ++p) for (int q = 'a'; q <= p; ++q) { if (i >= bad && j >= bad && p >= bad && q >= bad) continue; long long h = 123; if (k >= 1) h = h * 2184057 + i; if (k >= 2) h = h * 2184057 + j; if (k >= 3) h = h * 2184057 + p; if (k >= 4) h = h * 2184057 + q; if (S.count(h)) continue; S.insert(h); memset(allow, 0, sizeof(allow)); if (k >= 1) allow[i] = true; if (k >= 2) allow[j] = true; if (k >= 3) allow[p] = true; if (k >= 4) allow[q] = true; allow['S'] = allow['T'] = true; memset(d, -1, sizeof(d)); bfs(); if (d[fx][fy] == -1) continue; if (d[fx][fy] > res) continue; rest(); if (!rsf || cur < rs) { rsf = true, rs = cur; bad = -1; for (int t = 0; t < ((int)(cur).size()); ++t) bad = max(bad, (int)cur[t]); } } if (res == 100500100) res = -1; if (res == -1) cout << res << "\n"; else cout << rs.substr(1, ((int)(rs).size()) - 2) << "\n"; return 0; }
#include <bits/stdc++.h> using namespace std; int n, m, k, S, T, dir[4] = {1, -1}; char *grid; inline int dis(int i, int j) { return abs(i / m - j / m) + abs(i % m - j % m); } string dijkstra() { priority_queue<tuple<int, string, int, int>, vector<tuple<int, string, int, int> >, greater<tuple<int, string, int, int> > > q; set<pair<int, int> > vis; q.push(make_tuple(dis(S, T), "", 0, S)); while (!q.empty()) { auto c = q.top(); string path = get<1>(c); int i = get<3>(c); int mask = get<2>(c); q.pop(); if (vis.insert(make_pair(i, mask)).second) for (int j = 0; j < 4; j++) { int t = mask | (1 << (grid[i + dir[j]] - 'a')); if (grid[i + dir[j]] == 'S') continue; else if (grid[i + dir[j]] == 'T') return path; else if (__builtin_popcount(t) <= k && !vis.count(make_pair(i + dir[j], t))) q.push(make_tuple(dis(i + dir[j], T) + path.size() + 1, path + grid[i + dir[j]], t, i + dir[j])); } } return "-1"; } int main() { cin >> n >> m >> k; n += 2, dir[3] = -(dir[2] = m += 2); grid = (char *)malloc(n * m); memset(grid, 'S', n * m); for (int i = 1; i < n - 1; i++) for (int j = 1; j < m - 1; j++) { cin >> grid[i * m + j]; if (grid[i * m + j] == 'S') S = i * m + j; if (grid[i * m + j] == 'T') T = i * m + j; } cout << dijkstra() << endl; return 0; }
#include <bits/stdc++.h> using namespace std; template <typename T> int size(T& a) { return (int)a.size(); } const int MAXN = 51; const int INF = 1000000000; char s[MAXN][MAXN]; bool can[26]; int n, m, k; int sx, sy, fx, fy; int d[MAXN][MAXN]; bool used[MAXN][MAXN]; int dx[4] = {-1, 1, 0, 0}; int dy[4] = {0, 0, -1, 1}; bool valid(int y, int x) { return x >= 0 && y >= 0 && x < m && y < n && (s[y][x] == 'T' || s[y][x] == 'S' || can[s[y][x] - 'a']) && d[y][x] == INF; } struct Qu { int qx[MAXN * MAXN]; int qy[MAXN * MAXN]; int head, tail; Qu() { head = 0; tail = 0; } pair<int, int> pop() { int x = qx[tail]; int y = qy[tail]; ++tail; return make_pair(y, x); } void clear() { head = 0; tail = 0; } void operator=(const Qu& que) { head = que.head; for (int i = (0); i < (head); ++i) qx[i] = que.qx[i], qy[i] = que.qy[i]; } void push(int x, int y) { qx[head] = x; qy[head] = y; head++; } int size() { return head - tail; } }; Qu cur, nxt, Q; int ans = INF; string res = ""; void brute(int pos, int take) { if (pos == 26) { Q.clear(); for (int i = (0); i < (n); ++i) for (int j = (0); j < (m); ++j) d[i][j] = INF; if (can['y' - 'a']) { int br = 1; } d[fy][fx] = 0; Q.push(fx, fy); while (size(Q) > 0) { pair<int, int> p = Q.pop(); for (int u = (0); u < (4); ++u) if (valid(p.first + dy[u], p.second + dx[u])) { Q.push(p.second + dx[u], p.first + dy[u]); d[p.first + dy[u]][p.second + dx[u]] = d[p.first][p.second] + 1; } } if (d[sy][sx] == INF) return; string path = ""; cur.push(sx, sy); memset((used), (false), sizeof(used)); while (size(cur) > 0) { int minSymbol = INF; for (int i = (0); i < (size(cur)); ++i) { int x = cur.qx[i]; int y = cur.qy[i]; for (int u = (0); u < (4); ++u) { int nx = x + dx[u]; int ny = y + dy[u]; if (nx >= 0 && ny >= 0 && nx < m && ny < n && d[ny][nx] == d[y][x] - 1 && (s[ny][nx] == 'S' || s[ny][nx] == 'T' || can[s[ny][nx] - 'a'])) { minSymbol = min(minSymbol, (int)s[ny][nx]); } } } nxt.clear(); if (minSymbol != 'T') path += (char)(minSymbol); for (int i = (0); i < (size(cur)); ++i) { int x = cur.qx[i]; int y = cur.qy[i]; for (int u = (0); u < (4); ++u) { int nx = x + dx[u]; int ny = y + dy[u]; if (nx >= 0 && ny >= 0 && nx < m && ny < n && d[ny][nx] == d[y][x] - 1 && (s[ny][nx] == 'S' || s[ny][nx] == 'T' || can[s[ny][nx] - 'a']) && s[ny][nx] == minSymbol && !used[ny][nx]) { nxt.push(nx, ny); used[ny][nx] = true; } } } cur = nxt; } if (ans > d[sy][sx] || (ans == d[sy][sx] && res > path)) { ans = d[sy][sx]; res = path; } } else { if (take > 0) { can[pos] = true; brute(pos + 1, take - 1); } can[pos] = false; brute(pos + 1, take); } } void solve() { scanf("%d%d%d\n", &n, &m, &k); for (int i = (0); i < (n); ++i) { gets(s[i]); for (int j = (0); j < (m); ++j) if (s[i][j] == 'S') sx = j, sy = i; else if (s[i][j] == 'T') fx = j, fy = i; } brute(0, k); if (ans == INF) cout << "-1"; else printf("%s", res.c_str()); } int main() { solve(); }
#include <bits/stdc++.h> using namespace std; int n, m, q; int dx[] = {-1, 0, 0, 1}; int dy[] = {0, -1, 1, 0}; bool can[555]; bool vis[55][55]; char layout[55][55]; int dist[55][55]; int from[55][55]; int rnk[55][55]; char bst[2510]; vector<pair<int, int> > bpos[2510]; int sz[2510]; int sx, sy, tx, ty; inline bool legal(int i, int j) { return i && j && (i <= n && j <= m); } int res = 10000000; string op; void upd() { memset(dist, 0, sizeof(dist)); memset(vis, 0, sizeof(vis)); dist[tx][ty] = 1; queue<pair<int, int> > q; q.push(make_pair(tx, ty)); while (!q.empty()) { int cx = q.front().first, cy = q.front().second; q.pop(); for (int i = 3; ~i; --i) { int nx = cx + dx[i], ny = cy + dy[i]; if (legal(nx, ny) && !dist[nx][ny] && can[layout[nx][ny]]) { dist[nx][ny] = dist[cx][cy] + 1; q.push(make_pair(nx, ny)); } } } if (!dist[sx][sy] || dist[sx][sy] > res) return; string ans = ""; bst[1] = ' '; bpos[1].clear(); bpos[1].push_back(make_pair(sx, sy)); sz[1] = 1; vis[sx][sy] = 1; for (int i = 1; i < dist[sx][sy] - 1; ++i) { bst[i + 1] = 'z'; bpos[i + 1].clear(); for (int j = sz[i] - 1; ~j; --j) { int nx = bpos[i][j].first, ny = bpos[i][j].second; for (int k = 3; ~k; --k) { int tx = nx + dx[k], ty = ny + dy[k]; if (legal(tx, ty) && dist[tx][ty] == dist[nx][ny] - 1) { if (bst[i + 1] > layout[tx][ty]) bst[i + 1] = layout[tx][ty]; } } } sz[i + 1] = 0; ans += bst[i + 1]; for (int j = sz[i] - 1; ~j; --j) { int nx = bpos[i][j].first, ny = bpos[i][j].second; for (int k = 3; ~k; --k) { int tx = nx + dx[k], ty = ny + dy[k]; if (legal(tx, ty) && !vis[tx][ty] && dist[tx][ty] == dist[nx][ny] - 1 && bst[i + 1] == layout[tx][ty]) { bpos[i + 1].push_back(make_pair(tx, ty)); vis[tx][ty] = 1; ++sz[i + 1]; } } } } if (res > dist[sx][sy] || ans < op) { res = dist[sx][sy]; op = ans; } } int main(void) { scanf("%d%d%d", &n, &m, &q); for (int i = 1; i <= n; ++i) { scanf("%s", layout[i] + 1); for (int j = 1; j <= m; ++j) { if (layout[i][j] == 'S') { sx = i; sy = j; } if (layout[i][j] == 'T') { tx = i; ty = j; } } } can['S'] = 1; for (int i = 0; i < 26; ++i) { if (q == 1) { can[i + 'a'] = 1; upd(); can[i + 'a'] = 0; continue; } for (int j = i + 1; j < 26; ++j) { if (q == 2) { can[i + 'a'] = 1; can[j + 'a'] = 1; upd(); can[i + 'a'] = 0; can[j + 'a'] = 0; continue; } for (int k = j + 1; k < 26; ++k) { if (q == 3) { can[i + 'a'] = 1; can[j + 'a'] = 1; can[k + 'a'] = 1; upd(); can[i + 'a'] = 0; can[j + 'a'] = 0; can[k + 'a'] = 0; continue; } for (int l = k + 1; l < 26; ++l) { can[i + 'a'] = 1; can[j + 'a'] = 1; can[k + 'a'] = 1; can[l + 'a'] = 1; upd(); can[i + 'a'] = 0; can[j + 'a'] = 0; can[k + 'a'] = 0; can[l + 'a'] = 0; } } } } if (res > 1000000) { printf("-1"); return 0; } printf("%s", op.c_str()); return 0; }
#include <bits/stdc++.h> using namespace std; char table[51][51]; int dx[] = {1, 0, -1, 0, 1, 1, -1, -1}; int dy[] = {0, -1, 0, 1, 1, -1, -1, 1}; int mem[50][50][17903]; struct State { int r, c; int vis; int& ref() { return mem[r][c][vis]; } }; int stateToMask[18000]; int main(int argc, char* argv[]) { int N; cin >> N; int M; cin >> M; int K; cin >> K; int cnt = 0; set<int> m; for (int a = 0; a <= 'z' - 'a'; a++) { for (int b = 0; b <= a; b++) { for (int c = 0; c <= b; c++) { for (int d = 0; d <= c; d++) { int mask = (1 << a) | (1 << b) | (1 << c) | (1 << d); int bcnt = 1; if (b != a) bcnt++; if (c != a && c != b) bcnt++; if (d != c && d != a && d != b) bcnt++; if (bcnt != K) continue; if (m.find(mask) != m.end()) continue; m.insert(mask); stateToMask[cnt] = mask; cnt++; } } } } for (int i = 0; i < N; i++) scanf("%s", table[i]); memset(mem, -1, sizeof(mem)); State s; for (int i = 0; i < N; i++) { for (int j = 0; j < M; j++) { if (table[i][j] == 'T') { s.c = j; s.r = i; } } } queue<State> q; for (int mask = 0; mask < cnt; mask++) { s.vis = mask; s.ref() = 0; q.push(s); } while (!q.empty()) { State s = q.front(); q.pop(); int len = s.ref(); int mask = stateToMask[s.vis]; for (int k = 0; k < 4; k++) { State ns; ns.c = s.c + dx[k]; ns.r = s.r + dy[k]; ns.vis = s.vis; if (ns.c < 0 || ns.c >= M) continue; if (ns.r < 0 || ns.r >= N) continue; if (table[ns.r][ns.c] != 'S' && table[ns.r][ns.c] != 'T') { if ((mask & (1 << (table[ns.r][ns.c] - 'a'))) == 0) continue; } if (ns.ref() == -1) { ns.ref() = len + 1; q.push(ns); } } } int len = 1000000; for (int i = 0; i < N; i++) { for (int j = 0; j < M; j++) { if (table[i][j] == 'S') { s.c = j; s.r = i; } } } for (int i = 0; i < cnt; i++) { if (mem[s.r][s.c][i] != -1) { len = min(len, mem[s.r][s.c][i]); } } if (len == 1000000) { printf("-1\n"); return 0; } vector<State> qq; string ans; for (int vis = 0; vis < cnt; vis++) { s.vis = vis; if (mem[s.r][s.c][vis] == len) qq.push_back(s); } for (int i = 0; i < len - 1; i++) { char next = 'z' + 1; for (int j = 0; j < qq.size(); j++) { State s = qq[j]; int mask = stateToMask[s.vis]; for (int k = 0; k < 4; k++) { State ns; ns.c = s.c + dx[k]; ns.r = s.r + dy[k]; ns.vis = s.vis; if (ns.c < 0 || ns.c >= M) continue; if (ns.r < 0 || ns.r >= N) continue; if (table[ns.r][ns.c] != 'S' && table[ns.r][ns.c] != 'T') if (((mask & (1 << (table[ns.r][ns.c] - 'a')))) == 0) continue; if (ns.ref() + i == len - 1) { next = min(next, table[ns.r][ns.c]); } } } ans += next; vector<State> nq; for (int j = 0; j < qq.size(); j++) { State s = qq[j]; int mask = stateToMask[s.vis]; for (int k = 0; k < 4; k++) { State ns; ns.c = s.c + dx[k]; ns.r = s.r + dy[k]; ns.vis = s.vis; if (ns.c < 0 || ns.c >= M) continue; if (ns.r < 0 || ns.r >= N) continue; if (table[ns.r][ns.c] != 'S' && table[ns.r][ns.c] != 'T') if (((mask & (1 << (table[ns.r][ns.c] - 'a')))) == 0) continue; if (next == table[ns.r][ns.c] && ns.ref() + i == len - 1) { nq.push_back(ns); ns.ref() = -2; } } } nq.swap(qq); } printf("%s\n", ans.c_str()); return 0; }
#include <bits/stdc++.h> using namespace std; const int M = 100 + 10; char board[M][M]; char graph[M][M]; struct NODE { int parent_row; int parent_col; int dis; int visited; string par; } node[M][M]; int cnt = 0; int pattern[26 * 26 * 26 * 26][5]; void nchoosek(int num, int *a, int tar, int len, int isize, int spe) { if (isize == tar) { int j = 0; for (int i = 0; i < len; i++) { if (a[i] == 1) { pattern[cnt][j] = i; j++; } } cnt++; return; } else { for (int i = num; i < len; i++) { if (i != spe) { a[i] = 1; nchoosek(i + 1, a, tar, len, isize + 1, spe); a[i] = 0; } } return; } } string ans; int LEN = 1E+9; int dir[8] = {0, 1, 0, -1, -1, 0, 1, 0}; int n, m; void BFS(int sr, int sc, int er, int ec) { queue<pair<int, int> > Q; Q.push(make_pair(sr, sc)); node[sr][sc].visited = 1; node[sr][sc].dis = 0; while (!Q.empty()) { int row = Q.front().first; int col = Q.front().second; Q.pop(); for (int i = 0; i < 8; i = i + 2) { int nrow = row + dir[i]; int ncol = col + dir[i + 1]; if (nrow >= 0 && nrow < n && ncol >= 0 && ncol < m && (graph[nrow][ncol] == 'O' || graph[nrow][ncol] == 'T')) { if (node[nrow][ncol].visited == 1) { if (node[nrow][ncol].dis == node[row][col].dis + 1) { int prow = node[nrow][ncol].parent_row; int pcol = node[nrow][ncol].parent_col; if (node[row][col].par < node[prow][pcol].par) { node[nrow][ncol].parent_row = row; node[nrow][ncol].parent_col = col; node[nrow][ncol].par = node[row][col].par + board[nrow][ncol]; } } } else { node[nrow][ncol].parent_row = row; node[nrow][ncol].parent_col = col; node[nrow][ncol].dis = node[row][col].dis + 1; node[nrow][ncol].visited = 1; node[nrow][ncol].par = node[row][col].par + board[nrow][ncol]; if (nrow == er && ncol == ec) { ; } else { Q.push(make_pair(nrow, ncol)); } } } } } if (node[er][ec].visited == 1) { int row = er; int col = ec; vector<char> tmp; while (row != sr || col != sc) { tmp.push_back(board[row][col]); int irow = node[row][col].parent_row; int icol = node[row][col].parent_col; row = irow; col = icol; } tmp.push_back(board[sr][sc]); if (tmp.size() < LEN) { ans = ""; for (int i = tmp.size() - 1; i >= 0; i--) { ans = ans + tmp[i]; } LEN = tmp.size(); } else { if (tmp.size() == LEN) { string ss = ""; for (int i = tmp.size() - 1; i >= 0; i--) { ss += tmp[i]; } if (ss < ans) { ans = ss; } } } } return; } int main() { int k; cin >> n >> m >> k; set<char> letter; int sr, sc; int er, ec; for (int i = 0; i < n; i++) { string s; cin >> s; for (int j = 0; j < m; j++) { board[i][j] = s[j]; if (s[j] == 'S') { sr = i; sc = j; } if (s[j] == 'T') { er = i; ec = j; } if (s[j] != 'S' && s[j] != 'T') { letter.insert(s[j]); } } } vector<char> grid; for (set<char>::iterator it = letter.begin(); it != letter.end(); it++) { grid.push_back(*it); } sort(grid.begin(), grid.end()); if (grid.size() < k) { k = grid.size(); } for (int kk = 0; kk < 8; kk += 2) { int isr = sr + dir[kk]; int isc = sc + dir[kk + 1]; if (isr >= 0 && isr < n && isc >= 0 && isc < m) { for (int ksize = 1; ksize <= k; ksize++) { cnt = 0; int a[26]; for (int j = 0; j < grid.size(); j++) { a[j] = 0; } char cc = board[isr][isc]; int inum = -1; for (int ii = 0; ii < grid.size(); ii++) { if (grid[ii] == cc) { inum = ii; break; } } a[inum] = 1; nchoosek(0, a, ksize, grid.size(), 1, inum); for (int i = 0; i < cnt; i = i + 1) { for (int row = 0; row < n; row++) { for (int col = 0; col < m; col++) { if (board[row][col] == 'S') { graph[row][col] = 'S'; } if (board[row][col] == 'T') { graph[row][col] = 'T'; } if (board[row][col] != 'S' && board[row][col] != 'T') { graph[row][col] = 'X'; for (int j = 0; j < ksize; j++) { if (board[row][col] == grid[pattern[i][j]]) { graph[row][col] = 'O'; } } } } } for (int row = 0; row < n; row++) { for (int col = 0; col < m; col++) { node[row][col].visited = 0; } } for (int row = 0; row < n; row++) { for (int col = 0; col < m; col++) { node[row][col].visited = 0; } } BFS(isr, isc, er, ec); } } } } if (LEN == 1E+9) { if (n * m > 2) cout << "-1" << endl; } else { for (int i = 0; i < ans.size() - 1; i++) { cout << ans[i]; } cout << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; int xs, ys, xt, yt; int r, c, k, dist[55][55], ans, ok[30]; char mat[55][55]; bool help[55][55]; string str; void solve() { queue<pair<int, int> > q; memset(dist, 0x3f3f3f3f, sizeof(dist)); dist[xt][yt] = 0; q.push(pair<int, int>(xt, yt)); while (!q.empty()) { int i = q.front().first, j = q.front().second; q.pop(); if (i == xs && j == ys) break; if (i && dist[i - 1][j] == 0x3f3f3f3f && (mat[i - 1][j] == 'S' || ok[mat[i - 1][j] - 'a'])) { dist[i - 1][j] = dist[i][j] + 1; q.push(pair<int, int>(i - 1, j)); } if (i < r - 1 && dist[i + 1][j] == 0x3f3f3f3f && (mat[i + 1][j] == 'S' || ok[mat[i + 1][j] - 'a'])) { dist[i + 1][j] = dist[i][j] + 1; q.push(pair<int, int>(i + 1, j)); } if (j && dist[i][j - 1] == 0x3f3f3f3f && (mat[i][j - 1] == 'S' || ok[mat[i][j - 1] - 'a'])) { dist[i][j - 1] = dist[i][j] + 1; q.push(pair<int, int>(i, j - 1)); } if (j < c - 1 && dist[i][j + 1] == 0x3f3f3f3f && (mat[i][j + 1] == 'S' || ok[mat[i][j + 1] - 'a'])) { dist[i][j + 1] = dist[i][j] + 1; q.push(pair<int, int>(i, j + 1)); } } if (dist[xs][ys] == 0x3f3f3f3f || dist[xs][ys] > ans) return; vector<pair<int, int> > curr, next; char best, ch; string s; curr.push_back(pair<int, int>(xs, ys)); memset(help, false, sizeof(help)); for (int x = dist[xs][ys]; x > 0; x--) { best = 'z' + 1; for (int A = 0; A < curr.size(); A++) { int i = curr[A].first, j = curr[A].second; if (i && dist[i - 1][j] == x - 1 && !help[i - 1][j]) { ch = mat[i - 1][j]; if (ch < best) { best = ch; next.clear(); next.push_back(pair<int, int>(i - 1, j)); help[i - 1][j] = true; } else if (ch == best && !help[i - 1][j]) { next.push_back(pair<int, int>(i - 1, j)); help[i - 1][j] = true; } } if (i < r - 1 && dist[i + 1][j] == x - 1 && !help[i + 1][j]) { ch = mat[i + 1][j]; if (ch < best) { best = ch; next.clear(); next.push_back(pair<int, int>(i + 1, j)); help[i + 1][j] = true; } else if (ch == best && !help[i + 1][j]) { next.push_back(pair<int, int>(i + 1, j)); help[i + 1][j] = true; } } if (j && dist[i][j - 1] == x - 1 && !help[i][j - 1]) { ch = mat[i][j - 1]; if (ch < best) { best = ch; next.clear(); next.push_back(pair<int, int>(i, j - 1)); help[i][j - 1] = true; } else if (ch == best && !help[i][j - 1]) { next.push_back(pair<int, int>(i, j - 1)); help[i][j - 1] = true; } } if (j < c - 1 && dist[i][j + 1] == x - 1 && !help[i][j + 1]) { ch = mat[i][j + 1]; if (ch < best) { best = ch; next.clear(); next.push_back(pair<int, int>(i, j + 1)); help[i][j + 1] = true; } else if (ch == best && !help[i][j + 1]) { next.push_back(pair<int, int>(i, j + 1)); help[i][j + 1] = true; } } } if (best != 'T') s.push_back(best); curr.clear(); curr = next; } if (dist[xs][ys] < ans) { ans = dist[xs][ys]; str = s; } else if (dist[xs][ys] == ans && s < str) str = s; return; } void go(int x, int last) { if (x == k) { solve(); return; } for (int i = last + 1; i < 26; i++) if (!ok[i]) { ok[i] = 1; go(x + 1, i); ok[i] = 0; } return; } int main() { cin >> r >> c >> k; for (int i = 0; i < r; i++) cin >> mat[i]; for (int i = 0; i < r; i++) for (int j = 0; j < c; j++) { if (mat[i][j] == 'S') { xs = i; ys = j; } else if (mat[i][j] == 'T') { xt = i; yt = j; } } ans = 0x3f3f3f3f; memset(ok, 0, sizeof(ok)); go(0, -1); if (ans == 0x3f3f3f3f) cout << -1; else cout << str; cout << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 51; const int maxm = 26; const int dir[4][2] = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}}; struct Position { int x, y; }; Position st, en; int n, m, k; char mp[maxn][maxn]; bool hv[maxm], us[maxm]; int hc; string ph, th; int ml, tl; int sd[maxn][maxn], ed[maxn][maxn]; queue<Position> qe; bool Bound(Position p) { return p.x >= 0 && p.x < n && p.y >= 0 && p.y < m; } void Bfs(Position s, int dis[maxn][maxn]) { int i, j; Position nw, nx; for (i = 0; i < n; i++) { for (j = 0; j < m; j++) dis[i][j] = -1; } dis[s.x][s.y] = 0; qe.push(s); while (!qe.empty()) { nw = qe.front(); qe.pop(); for (i = 0; i < 4; i++) { nx.x = nw.x + dir[i][0]; nx.y = nw.y + dir[i][1]; if (Bound(nx) && dis[nx.x][nx.y] == -1) { if (!(mp[nx.x][nx.y] >= 'a' && mp[nx.x][nx.y] <= 'z' && us[mp[nx.x][nx.y] - 'a'] == 0)) { qe.push(nx); dis[nx.x][nx.y] = dis[nw.x][nw.y] + 1; } } } } } void FindPath() { vector<Position> tmp; Position nw, nx; char mi = 'z' + 1; int step = 1; int i; qe.push(st); while (!qe.empty()) { nw = qe.front(); qe.pop(); for (i = 0; i < 4; i++) { nx.x = nw.x + dir[i][0]; nx.y = nw.y + dir[i][1]; if (Bound(nx) && sd[nx.x][nx.y] == step && sd[nx.x][nx.y] + ed[nx.x][nx.y] == tl) { sd[nx.x][nx.y] = -1; if (mp[nx.x][nx.y] < mi) { mi = mp[nx.x][nx.y]; tmp.clear(); tmp.push_back(nx); } else if (mp[nx.x][nx.y] == mi) { tmp.push_back(nx); } } } if (qe.empty()) { if (tmp.empty()) break; while (!tmp.empty()) { qe.push(tmp.back()); tmp.pop_back(); } if (mi != 'T') th += mi; mi = 'z' + 1; step++; } } } void Run() { tl = -1; th = ""; Bfs(st, sd); Bfs(en, ed); if (sd[en.x][en.y] == -1) return; tl = sd[en.x][en.y]; FindPath(); if (ml == -1 || ml > tl || (ml == tl && ph > th)) { ml = tl; ph = th; } } void Select(int xp, int au) { if (au >= k) { Run(); return; } if (xp >= maxm) { return; } if (hv[xp]) { us[xp] = 1; Select(xp + 1, au + 1); us[xp] = 0; } Select(xp + 1, au); } int main() { int i, j; while (cin >> n >> m >> k) { for (i = 0; i < n; i++) cin >> mp[i]; memset(hv, 0, sizeof(hv)); for (i = 0; i < n; i++) { for (j = 0; j < m; j++) { if (mp[i][j] >= 'a' && mp[i][j] <= 'z') hv[mp[i][j] - 'a'] = 1; else if (mp[i][j] == 'S') st.x = i, st.y = j; else if (mp[i][j] == 'T') en.x = i, en.y = j; } } hc = 0; for (i = 0; i < maxm; i++) if (hv[i]) hc++; ml = -1; ph = ""; if (k >= hc) { for (i = 0; i < maxm; i++) us[i] = 1; Run(); } else { memset(us, 0, sizeof(us)); Select(0, 0); } if (ml == -1) cout << "-1" << endl; else cout << ph << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; const int inf(1010101010); const int dy[4] = {0, -1, 0, 1}; const int dx[4] = {1, 0, -1, 0}; string bin(int x, int le) { string ret; for (int i(0); i < (le); i++) ret += '0' + (x % 2), x /= 2; reverse((ret).begin(), (ret).end()); return ret; } int h, w; vector<string> veld(50); typedef int Mat[50][50]; Mat ds, dt; inline bool outofbounds(int y, int x) { return y >= h || y < 0 || x >= w || x < 0; } inline bool ok(char ch, int bm) { return ch == 'S' || ch == 'T' || bm & (1 << (ch - 'a')); } void bfs(int bm, pair<int, int> src, Mat& d) { for (int i(0); i < (h); i++) for (int j(0); j < (w); j++) d[i][j] = inf; d[src.first][src.second] = 0; deque<pair<int, int> > q; for (int i(0); i < (h); i++) for (int j(0); j < (w); j++) q.push_back(src); while (((int)(q).size())) { int y1(q.front().first), x1(q.front().second); q.pop_front(); for (int dir(0); dir < (4); dir++) { int y2(y1 + dy[dir]), x2(x1 + dx[dir]); if (!outofbounds(y2, x2) && (ok(veld[y2][x2], bm))) { int d2(d[y1][x1] + 1); if (d2 < d[y2][x2]) { d[y2][x2] = d2; q.push_back(make_pair(y2, x2)); } } } } } bool seen[55][55]; string bfs(int bm) { pair<int, int> s, t; for (int i(0); i < (h); i++) for (int j(0); j < (w); j++) { if (veld[i][j] == 'S') s = make_pair(i, j); if (veld[i][j] == 'T') t = make_pair(i, j); } bfs(bm, s, ds), bfs(bm, t, dt); int the_d(ds[t.first][t.second]); if (the_d == inf) { string ret; ret += 'z' + 1; return ret; } string pad; vector<pair<int, int> > doetmee; doetmee.push_back(s); for (int i(0); i < (50); i++) for (int j(0); j < (50); j++) seen[i][j] = false; seen[s.first][s.second] = true; while (true) { vector<pair<int, int> > doetmee2; assert(!((int)(doetmee2).size())); char nxt_chr('z'); for (__typeof((doetmee).end()) it((doetmee).begin()); it != (doetmee).end(); ++it) { int y1((*it).first), x1((*it).second); for (int dir(0); dir < (4); dir++) { int y2(y1 + dy[dir]), x2(x1 + dx[dir]); if (outofbounds(y2, x2)) continue; if (ds[y1][x1] + 1 + dt[y2][x2] == the_d) { if (y2 == t.first && x2 == t.second) { return pad; } nxt_chr = min(nxt_chr, veld[y2][x2]); doetmee2.push_back(make_pair(y2, x2)); } } } pad += nxt_chr; doetmee.clear(); for (__typeof((doetmee2).end()) it((doetmee2).begin()); it != (doetmee2).end(); ++it) { int y((*it).first), x((*it).second); if (veld[y][x] == nxt_chr) { if (!seen[y][x]) { doetmee.push_back(*it); seen[y][x] = true; } } } } } string min1(string const& a, string const& b) { if (((int)(a).size()) < ((int)(b).size())) return a; if (((int)(a).size()) > ((int)(b).size())) return b; return min(a, b); } int main() { int k; cin >> h >> w >> k; for (int i(0); i < (h); i++) cin >> veld[i]; string opt; for (int i(0); i < (1000); i++) opt += 'a'; const int A(26); for (int bm(0); bm < (1 << (A));) { if (__builtin_popcount(bm) < k) bm++; else { string ans(bfs(bm)); if (ans[0] != 'z' + 1) opt = min1(opt, ans); bm += bm & -bm; } } if (((int)(opt).size()) == 1000) { puts("-1"); } else { cout << opt << endl; } }
#include <bits/stdc++.h> using namespace std; template <typename T> int size(T& a) { return (int)a.size(); } const int MAXN = 51; const int INF = 1000000000; char s[MAXN][MAXN]; bool can[26]; int n, m, k; int sx, sy, fx, fy; int d[MAXN][MAXN]; bool used[MAXN][MAXN]; deque<pair<int, int> > Q; int dx[4] = {-1, 1, 0, 0}; int dy[4] = {0, 0, -1, 1}; bool valid(int y, int x) { return x >= 0 && y >= 0 && x < m && y < n && (s[y][x] == 'T' || s[y][x] == 'S' || can[s[y][x] - 'a']) && d[y][x] == INF; } struct Qu { int qx[MAXN * MAXN * 10]; int qy[MAXN * MAXN * 10]; int head; Qu() { head = 0; } void clear() { head = 0; } void operator=(const Qu& que) { head = que.head; for (int i = (0); i < (head); ++i) qx[i] = que.qx[i], qy[i] = que.qy[i]; } void push(int x, int y) { qx[head] = x; qy[head] = y; head++; } int size() { return head; } }; Qu cur, nxt; int ans = INF; string res = ""; void brute(int pos, int take) { if (pos == 26) { Q.clear(); for (int i = (0); i < (n); ++i) for (int j = (0); j < (m); ++j) d[i][j] = INF; d[fy][fx] = 0; Q.push_back(make_pair(fy, fx)); while (size(Q) > 0) { pair<int, int> p = Q.front(); Q.pop_front(); for (int u = (0); u < (4); ++u) if (valid(p.first + dy[u], p.second + dx[u])) { Q.push_back(make_pair(p.first + dy[u], p.second + dx[u])); d[p.first + dy[u]][p.second + dx[u]] = d[p.first][p.second] + 1; } } if (d[sy][sx] == INF) return; string path = ""; cur.push(sx, sy); memset((used), (false), sizeof(used)); while (size(cur) > 0) { int minSymbol = INF; for (int i = (0); i < (size(cur)); ++i) { int x = cur.qx[i]; int y = cur.qy[i]; for (int u = (0); u < (4); ++u) { int nx = x + dx[u]; int ny = y + dy[u]; if (nx >= 0 && ny >= 0 && nx < m && ny < n && d[ny][nx] == d[y][x] - 1 && (s[ny][nx] == 'S' || s[ny][nx] == 'T' || can[s[ny][nx] - 'a'])) { minSymbol = min(minSymbol, (int)s[ny][nx]); } } } nxt.clear(); if (minSymbol != 'T') path += (char)(minSymbol); for (int i = (0); i < (size(cur)); ++i) { int x = cur.qx[i]; int y = cur.qy[i]; for (int u = (0); u < (4); ++u) { int nx = x + dx[u]; int ny = y + dy[u]; if (nx >= 0 && ny >= 0 && nx < m && ny < n && d[ny][nx] == d[y][x] - 1 && (s[ny][nx] == 'S' || s[ny][nx] == 'T' || can[s[ny][nx] - 'a']) && s[ny][nx] == minSymbol && !used[ny][nx]) { nxt.push(nx, ny); used[ny][nx] = true; } } } cur = nxt; } if (ans > d[sy][sx] || (ans == d[sy][sx] && res > path)) { ans = d[sy][sx]; res = path; } } else { if (take > 0) { can[pos] = true; brute(pos + 1, take - 1); } can[pos] = false; brute(pos + 1, take); } } void solve() { scanf("%d%d%d\n", &n, &m, &k); for (int i = (0); i < (n); ++i) { gets(s[i]); for (int j = (0); j < (m); ++j) if (s[i][j] == 'S') sx = j, sy = i; else if (s[i][j] == 'T') fx = j, fy = i; } brute(0, k); if (ans == INF) cout << "-1"; else printf("%s", res.c_str()); } int main() { solve(); }
#include <bits/stdc++.h> using namespace std; const int oo = 0x3f3f3f3f; const double eps = 1e-9; int R, C, K, SX, SY, TX, TY; string grid[60], best; int dist[60][60]; vector<int> dir[60][60]; bool can[26]; int dx[] = {1, 0, -1, 0}, dy[] = {0, 1, 0, -1}; bool mark[60][60]; void bfs() { memset(dist, oo, sizeof(dist)); for (int i = (0); i < (R); i++) for (int j = (0); j < (C); j++) dir[i][j].clear(); dist[TX][TY] = 0; queue<pair<int, int> > q; q.push(pair<int, int>(TX, TY)); while (!q.empty()) { int r = q.front().first, c = q.front().second; q.pop(); if (grid[r][c] == 'S') break; for (int i = (0); i < (4); i++) { int rr = r + dx[i], cc = c + dy[i]; if (rr < 0 || rr == R || cc < 0 || cc == C) continue; if (grid[rr][cc] != 'S' && grid[rr][cc] != 'T' && !can[grid[rr][cc] - 'a']) continue; if (dist[rr][cc] < dist[r][c] + 1) continue; if (dist[rr][cc] > dist[r][c] + 1) { dist[rr][cc] = dist[r][c] + 1; dir[rr][cc].clear(); dir[rr][cc].push_back((i + 2) % 4); q.push(pair<int, int>(rr, cc)); } else { char ch = grid[rr + dx[dir[rr][cc][0]]][cc + dy[dir[rr][cc][0]]]; if (ch < grid[r][c]) continue; if (ch > grid[r][c]) dir[rr][cc].clear(); dir[rr][cc].push_back((i + 2) % 4); } } } if (dist[SX][SY] == oo) return; if (best != "0" && int((best).size()) < dist[SX][SY] - 1) return; string cur(dist[SX][SY] - 1, 'z'); vector<pair<int, int> > level; level.push_back(pair<int, int>(SX, SY)); memset(mark, 0, sizeof(mark)); mark[SX][SY] = true; for (int i = (0); i < (dist[SX][SY] - 1); i++) { for (int j = (0); j < (int((level).size())); j++) { int r = level[j].first, c = level[j].second; cur[i] = min(cur[i], grid[r + dx[dir[r][c][0]]][c + dy[dir[r][c][0]]]); } vector<pair<int, int> > nxt; for (int j = (0); j < (int((level).size())); j++) { int r = level[j].first, c = level[j].second; if (cur[i] != grid[r + dx[dir[r][c][0]]][c + dy[dir[r][c][0]]]) continue; for (int k = (0); k < (int((dir[r][c]).size())); k++) { int rr = r + dx[dir[r][c][k]], cc = c + dy[dir[r][c][k]]; if (!mark[rr][cc]) { mark[rr][cc] = true; nxt.push_back(pair<int, int>(rr, cc)); } } } level = nxt; } if (best == "0" || int((cur).size()) < int((best).size()) || (int((cur).size()) == int((best).size()) && cur < best)) best = cur; } void rek(int p, int k) { if (k < 0) return; if (p == 26) { if (k) return; bfs(); } else { can[p] = false; rek(p + 1, k); can[p] = true; rek(p + 1, k - 1); } } int main() { cin >> R >> C >> K; for (int i = (0); i < (R); i++) cin >> grid[i]; for (int i = (0); i < (R); i++) for (int j = (0); j < (C); j++) { if (grid[i][j] == 'S') { SX = i; SY = j; } if (grid[i][j] == 'T') { TX = i; TY = j; } } best = "0"; rek(0, K); if (best == "0") { cout << -1 << endl; } else { cout << best << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; int n, m, k; char in[55][55]; int used[300]; char ap[100], apc; string ans; int sx, sy; int ex, ey; int all[300], ac; int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1}; int que[3000][2]; int vis[55][55]; int dis[55][55]; int visid; vector<pair<int, int> > pos[2000]; inline void solve() { int i, j; visid++; int qs = 0, qe = 0; que[qe][0] = sx; que[qe][1] = sy; qe++; vis[sx][sy] = visid; dis[sx][sy] = 0; while (qs < qe) { int x = que[qs][0], y = que[qs][1]; qs++; for (i = 0; i < ac; i++) { for (j = 0; j < 4; j++) { int xx = x + dx[j], yy = y + dy[j]; if (xx >= 0 && xx < n && yy >= 0 && yy < m && vis[xx][yy] != visid && in[xx][yy] == all[i]) { que[qe][0] = xx; que[qe][1] = yy; qe++; vis[xx][yy] = visid; dis[xx][yy] = dis[x][y] + 1; } } } for (j = 0; j < 4; j++) { int xx = x + dx[j], yy = y + dy[j]; if (xx >= 0 && xx < n && yy >= 0 && yy < m && vis[xx][yy] != visid && in[xx][yy] == 'S') { que[qe][0] = xx; que[qe][1] = yy; qe++; vis[xx][yy] = visid; dis[xx][yy] = dis[x][y] + 1; } } } if (vis[ex][ey] != visid) return; string str; int d = dis[ex][ey]; pos[d].clear(); pos[d].push_back(make_pair(ex, ey)); visid++; vis[ex][ey] = visid; while (d > 1) { char c = 'z' + 1; for (i = 0; i < pos[d].size(); i++) { int x = pos[d][i].first, y = pos[d][i].second; for (j = 0; j < 4; j++) { int xx = x + dx[j], yy = y + dy[j]; if (xx >= 0 && xx < n && yy >= 0 && yy < m && vis[xx][yy] == visid - 1 && dis[xx][yy] == dis[x][y] - 1) { vis[xx][yy] = visid; if (in[xx][yy] < c) { c = in[xx][yy]; pos[d - 1].clear(); } if (in[xx][yy] == c) { pos[d - 1].push_back(make_pair(xx, yy)); } } } } str += c; d--; } if (str.size() < ans.size() || (str.size() == ans.size() && str < ans)) ans = str; } inline void dfs(int np, int c) { solve(); if (np == apc) return; dfs(np + 1, c); if (c < k) { all[ac++] = ap[np]; dfs(np + 1, c + 1); ac--; } } int main() { int i, j; scanf("%d%d%d", &n, &m, &k); for (i = 0; i < n; i++) scanf("%s", in[i]); for (i = 0; i < n; i++) for (j = 0; j < m; j++) { if (in[i][j] == 'S') ex = i, ey = j; if (in[i][j] == 'T') sx = i, sy = j; used[in[i][j]] = 1; } for (i = 'a'; i <= 'z'; i++) if (used[i]) ap[apc++] = i; for (int i = 0; i < 1000; i++) ans += 'z'; dfs(0, 0); if (ans.size() == 1000) puts("-1"); else puts(ans.c_str()); }
#include <bits/stdc++.h> using namespace std; const int MOD(1000000007); const int INF((1 << 30) - 1); const int MAXN(55); struct nnode { int x, y, d; string s; nnode(){}; nnode(int x, int y, int d, string s) : x(x), y(y), d(d), s(s){}; bool operator<(const nnode &other) const { if (d != other.d) return d > other.d; return s > other.s; } }; char a[MAXN][MAXN]; int n, m, k, path[MAXN][MAXN], available[26], ans; int d[4][2] = {1, 0, -1, 0, 0, 1, 0, -1}; pair<int, int> q[MAXN * MAXN]; string ansPath, p[MAXN][MAXN]; void SSSP() { int fr = 0, bk = 0; pair<int, int> s, t; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { path[i][j] = INF; p[i][j] = ""; if (a[i][j] == 'S') { s = pair<int, int>(i, j); } else if (a[i][j] == 'T') { t = pair<int, int>(i, j); q[bk++] = t; path[t.first][t.second] = 0; } } vector<pair<int, int> > b; while (fr != bk) { int x = q[fr].first, y = q[fr].second; fr++; b.push_back(pair<int, int>(x, y)); if (a[x][y] == 'S') break; for (int i = 0; i < 4; i++) { int tx = x + d[i][0]; int ty = y + d[i][1]; if (tx < 0 || tx >= n || ty < 0 || ty >= m) continue; if (a[tx][ty] == 'T') continue; if (a[tx][ty] != 'S' && !available[a[tx][ty] - 'a']) continue; if (path[x][y] + 1 < path[tx][ty]) { q[bk++] = pair<int, int>(tx, ty); path[tx][ty] = path[x][y] + 1; } } } if (path[s.first][s.second] == INF) return; p[s.first][s.second] = "S"; for (int i = (int)b.size() - 1; i >= 0; i--) { int x = b[i].first, y = b[i].second; if (p[s.first][s.second] == "") continue; for (int j = 0; j < 4; j++) { int tx = x + d[j][0]; int ty = y + d[j][1]; if (tx < 0 || tx >= n || ty < 0 || ty >= m) continue; if (path[x][y] - 1 == path[tx][ty]) { if (p[tx][ty] == "") p[tx][ty] = p[x][y] + a[tx][ty]; else p[tx][ty] = min(p[tx][ty], p[x][y] + a[tx][ty]); } } } if (path[s.first][s.second] < ans || (path[s.first][s.second] == ans && p[t.first][t.second] < ansPath)) { ans = path[s.first][s.second]; ansPath = p[t.first][t.second]; } } void combination(int now, int i) { if (now == k) { SSSP(); return; } while (i < 26) { available[i] = 1; combination(now + 1, i + 1); available[i] = 0; i++; } } int main() { scanf("%d%d%d", &n, &m, &k); for (int i = 0; i < n; i++) scanf("%s", a[i]); ans = INF; ansPath = ""; combination(0, -1); if (ans == INF) printf("-1"); else cout << ansPath.substr(1, ansPath.size() - 2); }
#include <bits/stdc++.h> using namespace std; inline int GetBit(int mask, int num) { return (mask >> num) & 1; } inline int GetAmountOfBits(int mask) { int ans = 0; while (mask > 0) { ans += (mask & 1); mask >>= 1; } return ans; } const int kAlphabetSize = 26; const int kDx[4] = {-1, 0, 0, 1}; const int kDy[4] = {0, -1, 1, 0}; int n, m, k; vector<vector<char> > field; int si, sj; int fi, fj; bool ans_found; int ans_len; string ans_path; vector<vector<bool> > used; vector<vector<bool> > inused; vector<vector<int> > dist; vector<int> char_posses_i[kAlphabetSize]; vector<int> char_posses_j[kAlphabetSize]; void ClearUsed(int mask, vector<vector<bool> >& used) { for (int c = 0; c < kAlphabetSize; ++c) { if (!GetBit(mask, c)) { continue; } for (int i = 0; i < (int)char_posses_i[c].size(); ++i) { used[char_posses_i[c][i]][char_posses_j[c][i]] = false; } } used[si][sj] = false; used[fi][fj] = false; } void UpdateAns(int mask) { if (dist[fi][fj] == 1) { ans_found = true; ans_len = 1; ans_path = ""; return; } string cur_path; cur_path.reserve(dist[fi][fj] - 1); deque<int> qi; deque<int> qj; qi.push_back(fi); qj.push_back(fj); inused[fi][fj] = true; while (!qi.empty()) { int ci = qi.front(); qi.pop_front(); int cj = qj.front(); qj.pop_front(); for (int step_index = 0; step_index < 4; ++step_index) { int ni = ci + kDx[step_index]; int nj = cj + kDy[step_index]; if (ni >= 0 && ni < n && nj >= 0 && nj < m && !inused[ni][nj] && used[ni][nj] && dist[ni][nj] + 1 == dist[ci][cj]) { inused[ni][nj] = true; qi.push_back(ni); qj.push_back(nj); } } } qi.push_back(si); qj.push_back(sj); used[si][sj] = false; while (!qi.empty()) { char min_char = field[qi[0]][qj[0]]; for (int i = 1; i < (int)qi.size(); ++i) { min_char = min(min_char, field[qi[i]][qj[i]]); } if (min_char != 'S' && min_char != 'T') { cur_path.push_back(min_char); } int sz = qi.size(); for (int itr = 0; itr < (int)sz; ++itr) { int ci = qi.front(); qi.pop_front(); int cj = qj.front(); qj.pop_front(); if (field[ci][cj] != min_char) { continue; } for (int step_index = 0; step_index < 4; ++step_index) { int ni = ci + kDx[step_index]; int nj = cj + kDy[step_index]; if (ni >= 0 && ni < n && nj >= 0 && nj < m && inused[ni][nj] && used[ni][nj] && dist[ni][nj] == dist[ci][cj] + 1) { used[ni][nj] = false; qi.push_back(ni); qj.push_back(nj); } } } } ClearUsed(mask, inused); if (!ans_found || dist[fi][fj] < ans_len || cur_path < ans_path) { ans_found = true; ans_len = dist[fi][fj]; ans_path = cur_path; } } void Solve(int mask) { queue<int> qi; queue<int> qj; used[si][sj] = true; dist[si][sj] = 0; qi.push(si); qj.push(sj); while (!qi.empty()) { int ci = qi.front(); qi.pop(); int cj = qj.front(); qj.pop(); for (int step_index = 0; step_index < 4; ++step_index) { int ni = ci + kDx[step_index]; int nj = cj + kDy[step_index]; if (ni >= 0 && ni < n && nj >= 0 && nj < m && (field[ni][nj] == 'T' || field[ni][nj] == 'S' || GetBit(mask, field[ni][nj] - 'a')) && !used[ni][nj]) { used[ni][nj] = true; dist[ni][nj] = dist[ci][cj] + 1; qi.push(ni); qj.push(nj); } } } if (used[fi][fj]) { if (!ans_found || dist[fi][fj] <= ans_len) { UpdateAns(mask); } } ClearUsed(mask, used); } void Dfs(int c, int mask, int num) { if (c == kAlphabetSize) { Solve(mask); return; } if (num + 1 <= k) { Dfs(c + 1, mask + (1 << c), num + 1); } Dfs(c + 1, mask, num); } int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); cin >> n >> m >> k; field.resize(n, vector<char>(m)); for (int i = 0; i < n; ++i) { for (int j = 0; j < m; ++j) { cin >> field[i][j]; if (field[i][j] == 'S') { si = i; sj = j; } if (field[i][j] == 'T') { fi = i; fj = j; } } } used.assign(n, vector<bool>(m, false)); inused.assign(n, vector<bool>(m, false)); dist.resize(n, vector<int>(m)); for (int i = 0; i < n; ++i) { for (int j = 0; j < m; ++j) { if (field[i][j] >= 'a' && field[i][j] <= 'z') { char_posses_i[field[i][j] - 'a'].push_back(i); char_posses_j[field[i][j] - 'a'].push_back(j); } } } ans_found = false; Dfs(0, 0, 0); if (!ans_found) { cout << -1 << endl; } else { cout << ans_path << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; int n, m, k, S, T; char s[2555]; vector<int> adj[2555]; int val[2555], d[2555], p[2555]; string ans; void check(int x) { string now; for (; d[x]; x = p[x]) now += s[x]; reverse(now.begin(), now.end()); if (now.length() < ans.length()) ans = now; else if (now.length() == ans.length() && now < ans) ans = now; } bool cmp_val(int i, int j) { return val[i] < val[j]; } void solve(int mask) { memset(d, -1, sizeof d); vector<int> u, v; d[S] = 0, val[S] = 0, u.push_back(S); while (!u.empty()) { v.clear(); for (int i = 0; i < u.size(); i++) { int x = u[i]; for (int j = 0; j < adj[x].size(); j++) { int y = adj[x][j]; if (y == T) { check(x); return; } if (d[y] != -1 || !(mask >> (s[y] - 'a') & 1)) continue; d[y] = d[x] + 1, p[y] = x, val[y] = val[x] * 2555 + s[y], v.push_back(y); } } sort(v.begin(), v.end(), cmp_val); for (int i = 0, prv; i < v.size(); i++) { if (i == 0) prv = val[v[0]], val[v[0]] = 0; else { int tmp = val[v[i]]; val[v[i]] = val[v[i - 1]] + (tmp != prv); prv = tmp; } } u = v; } } bool good(int i, int j) { return 0 <= i && i < n && 0 <= j && j < m; } int node(int i, int j) { return i * m + j; } bool cmp_s(int i, int j) { return s[i] < s[j]; } int main() { scanf("%d%d%d", &n, &m, &k); for (int i = 0; i < n; i++) scanf("%s", s + i * m); ans = string(3000, 'a'); for (int i = 0; i < n * m; i++) { if (s[i] == 'S') S = i; if (s[i] == 'T') T = i; } for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { if (good(i + 1, j)) adj[node(i, j)].push_back(node(i + 1, j)); if (good(i - 1, j)) adj[node(i, j)].push_back(node(i - 1, j)); if (good(i, j + 1)) adj[node(i, j)].push_back(node(i, j + 1)); if (good(i, j - 1)) adj[node(i, j)].push_back(node(i, j - 1)); } for (int i = 0; i < n * m; i++) sort(adj[i].begin(), adj[i].end(), cmp_s); for (int i = 0; i < (1 << 26); i++) if (__builtin_popcount(i) == k) solve(i); if (ans.length() == 3000) ans = "-1"; cout << ans << endl; }
#include <bits/stdc++.h> #pragma warning(disable : 4996) using namespace std; const int MAXN = 55; struct Node { int sta, pos; string path; Node(string _path, int _sta, int _pos) : path(_path), sta(_sta), pos(_pos) {} bool operator<(const Node& v) const { int len = path.size(); int lenb = v.path.size(); if (len != lenb) return len > lenb; if (path < v.path) return false; if (path > v.path) return true; return pos < v.pos; } }; int n, m, K; int si, sj; static int dir[4][2] = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}}; char mat[MAXN][MAXN]; int visited[MAXN][MAXN]; set<long long> s; void InputMat() { for (int i = 0; i < n; i++) { while (getchar() != '\n') ; for (int j = 0; j < m; j++) { mat[i][j] = getchar(); if (mat[i][j] == 'S') { si = i; sj = j; } } } } int iCount(int x) { int ret = 0; for (; x; x &= x - 1) ret++; return ret; } bool legal(int x, int y) { return x >= 0 && x < n && y >= 0 && y < m && mat[x][y] != 'S'; } string Bfs() { priority_queue<Node> q; memset(visited, 0, sizeof(visited)); s.clear(); q.push(Node("", 0, si * m + sj)); s.insert(si * m + sj); while (!q.empty()) { Node u = q.top(); q.pop(); for (int k = 0; k < 4; k++) { int nx = u.pos / m + dir[k][0]; int ny = u.pos % m + dir[k][1]; if (legal(nx, ny) == false) continue; if (mat[nx][ny] == 'T') { return u.path; } if (!(u.sta & (1 << (mat[nx][ny] - 'a'))) && iCount(u.sta) == K) continue; Node v = Node(u.path + mat[nx][ny], u.sta | (1 << (mat[nx][ny] - 'a')), nx * m + ny); long long tmp = v.sta * 10000 + v.pos; if (s.find(tmp) != s.end()) continue; if (visited[nx][ny] && (visited[nx][ny] & v.sta) == visited[nx][ny]) continue; visited[nx][ny] = v.sta; s.insert(tmp); q.push(v); } } return "-1"; } int main() { string Ans; scanf("%d %d %d", &n, &m, &K); InputMat(); Ans = Bfs(); printf("%s\n", Ans.c_str()); return 0; }
#include <bits/stdc++.h> using namespace std; const int MAXN = 55, dx[4] = {0, 0, -1, 1}, dy[4] = {1, -1, 0, 0}; int n, m, k, dis[MAXN][MAXN], sx, sy, tx, ty; queue<pair<int, int> > S; char mp[MAXN][MAXN]; string ans, res; bool r[27], o; bool isval(int x, int y) { return x < n && y < m && x >= 0 && y >= 0; } void BFS(vector<pair<int, int> > w) { vector<pair<int, int> > rx[27]; for (int ii = 0; ii < w.size(); ii++) { int x = w[ii].first, y = w[ii].second; for (int i = 0; i < 4; i++) { int nx = x + dx[i], ny = y + dy[i]; if (!isval(nx, ny) || (!r[mp[nx][ny] - 'a'] && mp[nx][ny] != 'T') || dis[nx][ny] + 1 != dis[x][y]) continue; if (mp[nx][ny] == 'T') return; rx[mp[nx][ny] - 'a'].push_back({nx, ny}); } } for (int i = 0; i < 27; i++) { sort(rx[i].begin(), rx[i].end()); rx[i].resize(unique(rx[i].begin(), rx[i].end()) - rx[i].begin()); if (rx[i].size() == 0) continue; BFS(rx[i]); res += (char)('a' + i); return; } } void solve() { res.clear(); for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) dis[i][j] = -1; S.push({tx, ty}); dis[tx][ty] = 0; while (!S.empty()) { pair<int, int> c = S.front(); S.pop(); for (int i = 0; i < 4; i++) { int nx = c.first + dx[i], ny = c.second + dy[i]; if (!isval(nx, ny) || (mp[nx][ny] != 'S' && mp[nx][ny] != 'T' && !r[mp[nx][ny] - 'a'])) continue; if (dis[nx][ny] == -1) { S.push({nx, ny}); dis[nx][ny] = dis[c.first][c.second] + 1; } } } if (dis[sx][sy] == -1) return; vector<pair<int, int> > vc; vc.push_back({sx, sy}); BFS(vc); reverse(res.begin(), res.end()); if (!o) ans = res, o = 1; else { if (ans.size() < res.size()) return; if (ans.size() > res.size()) ans = res; else ans = min(ans, res); } } void bt(int ind, int rem) { if (ind == 26) { solve(); return; } if (rem > 0) { r[ind] = 1; bt(ind + 1, rem - 1); } r[ind] = 0; bt(ind + 1, rem); } int main() { cin >> n >> m >> k; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { cin >> mp[i][j]; if (mp[i][j] == 'S') sx = i, sy = j; else if (mp[i][j] == 'T') tx = i, ty = j; } bt(0, k); if (!o) cout << -1 << endl; else cout << ans << endl; }
#include <bits/stdc++.h> using namespace std; char A[53][53]; int q[(4 * 15000)]; int dist[53][53]; int dr[] = {-1, 0, 0, 1}; int dc[] = {0, -1, 1, 0}; int sz(int s) { int ans = 0; while (s) ans += s & 1, s >>= 1; return ans; } int N, M, K; bool marked[53][53]; void mark(int i, int j) { if (marked[i][j]) return; marked[i][j] = true; for (int mv = 0; mv < (4); ++mv) { int i2 = i + dr[mv]; int j2 = j + dc[mv]; if (i2 < 0 || i2 >= N) continue; if (j2 < 0 || j2 >= M) continue; if (marked[i2][j2]) continue; if (dist[i2][j2] < 0) continue; if (dist[i2][j2] == dist[i][j] - 1) mark(i2, j2); } } int main() { cin >> N >> M >> K; for (int i = 0; i < (N); ++i) scanf("%s", A[i]); int seen = 0; int ti = -1, tj = -1; int si = -1, sj = -1; for (int i = 0; i < (N); ++i) for (int j = 0; j < (M); ++j) if (A[i][j] == 'T') ti = i, tj = j; else if (A[i][j] == 'S') si = i, sj = j; else seen |= 1 << (A[i][j] - 'a'); assert(si >= 0 && sj >= 0); assert(ti >= 0 && tj >= 0); int h = 0, t = -1; int S = 1 << 26; for (int s = 0; s < (S); ++s) { if ((s | seen) > seen) continue; if (sz(s) > K) continue; q[++t] = s; assert(t < (4 * 15000)); } string ans(N * M + 1, 'z'); while (h <= t) { int s = q[h++]; queue<int> Q; Q.push(((si)*50 + (sj))); memset(dist, -1, sizeof(dist)); dist[si][sj] = 0; while (!Q.empty()) { int n = Q.front(); Q.pop(); int i = ((n) / 50), j = ((n) % 50); if (i == ti && j == tj) break; assert(dist[i][j] >= 0); for (int mv = 0; mv < (4); ++mv) { int i2 = i + dr[mv]; int j2 = j + dc[mv]; if (i2 < 0 || i2 >= N) continue; if (j2 < 0 || j2 >= M) continue; if (A[i2][j2] != 'T' && !(s & (1 << (A[i2][j2] - 'a')))) continue; if (dist[i2][j2] < 0 || dist[i][j] + 1 < dist[i2][j2]) { dist[i2][j2] = dist[i][j] + 1; Q.push(((i2)*50 + (j2))); } } } if (dist[ti][tj] < 0 || dist[ti][tj] > (int)ans.size() + 1) continue; memset(marked, 0, sizeof(marked)); mark(ti, tj); vector<int> now; vector<int> next; string path; char nextc; now.push_back(((si)*50 + (sj))); while (!now.empty()) { next.clear(); nextc = 'z' + 1; int m = now.size(); for (int x = 0; x < (m); ++x) { int n = now[x]; int i = ((n) / 50), j = ((n) % 50); for (int mv = 0; mv < (4); ++mv) { int i2 = i + dr[mv]; int j2 = j + dc[mv]; if (i2 < 0 || i2 >= N) continue; if (j2 < 0 || j2 >= M) continue; if (!marked[i2][j2]) continue; if (dist[i2][j2] != dist[i][j] + 1) continue; char c = A[i2][j2]; if (c < nextc) nextc = c; } } for (int x = 0; x < (m); ++x) { int n = now[x]; int i = ((n) / 50), j = ((n) % 50); for (int mv = 0; mv < (4); ++mv) { int i2 = i + dr[mv]; int j2 = j + dc[mv]; if (i2 < 0 || i2 >= N) continue; if (j2 < 0 || j2 >= M) continue; if (!marked[i2][j2]) continue; if (dist[i2][j2] != dist[i][j] + 1) continue; char c = A[i2][j2]; if (c != nextc) continue; next.push_back(((i2)*50 + (j2))); } } sort(next.begin(), next.end()); next.erase(unique(next.begin(), next.end()), next.end()); swap(now, next); if (!now.empty()) path += nextc; } assert((int)path.length() == dist[ti][tj] && dist[ti][tj] >= 1); path = path.substr(0, dist[ti][tj] - 1); if (path.length() < ans.length() || (path.length() == ans.length() && path < ans)) { ans = path; } } if ((int)ans.length() <= N * M) cout << ans << endl; else cout << -1 << endl; }
#include <bits/stdc++.h> using namespace std; struct Node { int cnt = 1, key, prior; long long sum[5] = {}; Node *left = NULL, *right = NULL; }; typedef Node *PNode; Node nodes[111111]; int pri[111111]; int nodeCount = 0; inline int cnt(PNode &v) { return v ? v->cnt : 0; } inline void update(PNode &v) { if (v) { v->cnt = cnt(v->left) + cnt(v->right) + 1; int off = 0; if (v->left) { for (int i = 0; i < (int)(5); ++i) v->sum[i] = v->left->sum[i]; off = v->left->cnt % 5; } else { for (int i = 0; i < (int)(5); ++i) v->sum[i] = 0; } v->sum[off] += v->key; if (++off == 5) off = 0; if (v->right) { for (int i = 0; i < (int)(5); ++i) { int ii = i + off; if (ii >= 5) ii -= 5; v->sum[ii] += v->right->sum[i]; } } } } void merge(PNode l, PNode r, PNode &t) { if (!l || !r) { t = l ? l : r; return; } if (l->prior > r->prior) { merge(l->right, r, l->right); t = l; } else { merge(l, r->left, r->left); t = r; } update(t); } void split(PNode t, PNode &l, PNode &r, int key) { if (!t) { l = r = NULL; return; } if (key < t->key) { split(t->left, l, t->left, key); r = t; } else { split(t->right, t->right, r, key); l = t; } update(t); } PNode root = NULL; void addKey(int x) { PNode t1, t2, t3; split(root, t1, t3, x); nodes[nodeCount].key = x; nodes[nodeCount].prior = pri[nodeCount]; t2 = nodes + nodeCount++; update(t2); merge(t1, t2, root); merge(root, t3, root); } void delKey(PNode &t, int x) { if (t->key == x) { merge(t->left, t->right, t); } else if (x < t->key) { delKey(t->left, x); } else { delKey(t->right, x); } update(t); } mt19937 mt; int myRand(int bound) { return mt() % bound; } char s[10]; int zzz; int main() { for (int i = 0; i < (int)(111111); ++i) pri[i] = i; random_shuffle(pri, pri + 111111, myRand); int q; scanf("%d", &q); for (int query = 0; query < (int)(q); ++query) { scanf("%s", s); if (s[0] == 'a') { scanf("%d", &zzz); addKey(zzz); } else if (s[0] == 'd') { scanf("%d", &zzz); delKey(root, zzz); } else { if (root == NULL) { printf("0\n"); } else { printf("%I64d\n", root->sum[2]); } } } return 0; }
#include <bits/stdc++.h> using namespace std; const int SIZ = 1 << 17; const int MAXN = 100100; long long tot[SIZ * 2], cou[SIZ * 2][5]; int n; string instr[MAXN]; long long v[MAXN]; long long lis[MAXN]; int t; map<long long, int> lookup; void fix(int p) { while (p != 1) { p /= 2; tot[p] = tot[p * 2] + tot[p * 2 + 1]; for (int i = (0); i < (5); i++) { cou[p][i] = cou[p * 2][i]; } int shift = tot[p * 2] % 5LL; for (int i = (0); i < (5); i++) { cou[p][(i + shift) % 5] += cou[p * 2 + 1][i]; } } } int main() { memset(tot, 0, sizeof(tot)); memset(cou, 0, sizeof(cou)); cin >> n; t = 0; for (int i = (0); i < (n); i++) { cin >> instr[i]; if (instr[i] == "add" || instr[i] == "del") { cin >> v[i]; lis[t++] = v[i]; } } sort(lis, lis + t); int t1 = 0; lookup.clear(); for (int i = (0); i < (t); i++) { if (i > 0 && lis[i] != lis[i - 1]) t1++; lookup[lis[i]] = t1; } for (int i = (0); i < (n); i++) { if (instr[i] == "add") { int p = SIZ + lookup[v[i]]; cou[p][1] = v[i]; tot[p] = 1; fix(p); } if (instr[i] == "del") { int p = SIZ + lookup[v[i]]; cou[p][1] = 0; tot[p] = 0; fix(p); } if (instr[i] == "sum") { cout << cou[1][3] << "\n"; } } return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = 1e9; inline int pt(int a[], int l, int r) { int p, i, j; p = a[l]; i = l; j = r + 1; for (;;) { while (a[++i] < p) if (i >= r) break; while (a[--j] > p) if (j <= l) break; if (i >= j) break; else swap(a[i], a[j]); } if (j == l) return j; swap(a[l], a[j]); return j; } inline void q_sort(int a[], int l, int r) { int q; if (r > l) { q = pt(a, l, r); q_sort(a, l, q - 1); q_sort(a, q + 1, r); } } inline void rd(int &val) { int x = 0; int f = 1; char ch = getchar(); while (ch < '0' || ch > '9') ch = getchar(); if (ch == '-') { f = -1; ch = getchar(); } while (ch >= '0' && ch <= '9') { x = x * 10 + ch - '0'; ch = getchar(); } val = x * f; } inline void quickSort(int s[], int l, int r) { if (l < r) { int i = l, j = r, x = s[l]; while (i < j) { while (i < j && s[j] >= x) j--; if (i < j) s[i++] = s[j]; while (i < j && s[i] < x) i++; if (i < j) s[j--] = s[i]; } s[i] = x; quickSort(s, l, i - 1); quickSort(s, i + 1, r); } } int n; vector<int> v; int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); int i, j, x; string t; cin >> n; for (i = 0; i < n; i++) { cin >> t; if (t == "add") { cin >> x; v.insert(lower_bound(v.begin(), v.end(), x), x); } else if (t == "del") { cin >> x; v.erase(lower_bound(v.begin(), v.end(), x)); } else if (t == "sum") { long long ans = 0; for (j = 2; j < v.size(); j += 5) ans += v[j]; cout << ans << endl; } } return 0; }
#include <bits/stdc++.h> using namespace std; struct Node { int v, size, fix; long long sum[5]; Node *left, *right; Node() {} Node(int _v, Node *l = NULL, Node *r = NULL) { v = _v, fix = rand(), left = l, right = r; memset(sum, 0, sizeof(sum)); sum[0] = v, size = 1; } int lsize() { return left == NULL ? 0 : left->size; } int rsize() { return right == NULL ? 0 : right->size; } void Push_up() { memset(sum, 0, sizeof(sum)); size = 0; if (left != NULL) { for (int i = 0; i < 5; i++) { sum[i] = left->sum[i]; } } size = lsize(), sum[size % 5] += v, size++; if (right != NULL) { for (int i = 0; i < 5; i++) { sum[(size + i) % 5] += right->sum[i]; } } size += rsize(); } } *T = NULL; typedef pair<Node *, Node *> pnn; void print(Node *T, int v, int p) { if (T == NULL) return; for (int i = 0; i < v; i++) { printf(" "); } string s = p == 0 ? "root" : p == 1 ? "left" : "right"; printf("%s:%d sum:", s.c_str(), T->v); for (int i = 0; i < 5; i++) { printf("%I64d ", T->sum[i]); } printf("\n"); print(T->left, v + 1, 1), print(T->right, v + 1, 2); } Node *merge(Node *l, Node *r) { if (l == NULL || r == NULL) { return l == NULL ? r : l; } if (l->fix < r->fix) { l->right = merge(l->right, r); l->Push_up(); return l; } r->left = merge(l, r->left); r->Push_up(); return r; } pnn split(Node *T, int v) { if (T == NULL) return make_pair<Node *, Node *>(NULL, NULL); if (v > T->v) { pnn t = split(T->right, v); Node *l = T, *r = t.second; l->right = t.first, l->Push_up(); return make_pair(l, r); } pnn t = split(T->left, v); Node *l = t.first, *r = T; r->left = t.second, r->Push_up(); return make_pair(l, r); } void add(int x) { pnn t = split(T, x); T = merge(t.first, merge(new Node(x), t.second)); } void del(int x) { pnn t1 = split(T, x); pnn t2 = split(t1.second, x + 1); if (t2.first != NULL) delete t2.first; T = merge(t1.first, t2.second); } long long sum() { return T == NULL ? 0 : T->sum[2]; } char buf[10]; string read() { scanf("%s", buf); return buf; } int main() { srand((int)time(NULL)); int n; scanf("%d", &n); for (int i = 0; i < n; i++) { string op = read(); int x; if (op == "add") { scanf("%d", &x); add(x); } if (op == "del") { scanf("%d", &x); del(x); } if (op == "sum") { printf("%I64d\n", sum()); } } return 0; }
#include <bits/stdc++.h> using namespace std; struct Node { Node *l, *r; int a; const int h; int size; long long sum[5]; Node(int a) : l(NULL), r(NULL), a(a), h(rand()), size(0) { for (int i = 0; i < 5; ++i) { sum[i] = 0LL; } } static int psize(Node* p) { return p == NULL ? 0 : p->size; } static long long psum(Node* p, int i) { return p == NULL ? 0 : p->sum[i]; } void upd() { size = 1 + psize(l) + psize(r); for (int i = 0; i < 5; ++i) { sum[i] = psum(l, i); } sum[psize(l) % 5] += a; for (int i = 0; i < 5; ++i) { sum[(i + psize(l) + 1) % 5] += psum(r, i); } } ~Node() { delete l; delete r; } }; Node* zig(Node* p) { Node* t = p->l; p->l = t->r; t->r = p; p->upd(); t->upd(); return t; } Node* zag(Node* p) { Node* t = p->r; p->r = t->l; t->l = p; p->upd(); t->upd(); return t; } Node* insert(Node* p, int a) { if (p == NULL) { p = new Node(a); } else if (a < p->a) { p->l = insert(p->l, a); if (p->l->h < p->h) { p = zig(p); } } else { p->r = insert(p->r, a); if (p->r->h < p->h) { p = zag(p); } } p->upd(); return p; } Node* merge(Node* l, Node* r) { if (l == NULL) { return r; } else if (r == NULL) { return l; } else if (l->h < r->h) { l->r = merge(l->r, r); l->upd(); return l; } else { r->l = merge(l, r->l); r->upd(); return r; } } Node* remove(Node* p, int a) { if (p == NULL) { return NULL; } else if (a < p->a) { p->l = remove(p->l, a); p->upd(); } else if (a > p->a) { p->r = remove(p->r, a); p->upd(); } else { Node* t = p; p = merge(p->l, p->r); t->l = t->r = NULL; delete t; } return p; } int main() { int n, a; cin >> n; char str[10]; Node* p = NULL; while (n--) { scanf("%s", str); if (str[0] == 'a') { scanf("%d", &a); p = insert(p, a); } else if (str[0] == 'd') { scanf("%d", &a); p = remove(p, a); } else printf("%I64d\n", p == NULL ? 0LL : p->sum[2]); } return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 100010; long long n, x, tree[N << 3][5], add[N << 2], pan[N << 2], shu[N << 2]; long long num[N << 3]; string a; map<int, int> id; void pushup(int k) { num[k] = num[k * 2] + num[k * 2 + 1]; for (long long j = 0; j <= 4; ++j) tree[k][j] = tree[k * 2][j] + tree[k * 2 + 1][((j - num[k * 2]) % 5 + 5) % 5]; } void update(long long l, long long r, long long k, long long wei, long long wor, long long sum) { if (l == r) { tree[k][1] += wor; num[k] += sum; return; } long long mid = (l + r) >> 1; if (wei <= mid) update(l, mid, k * 2, wei, wor, sum); else update(mid + 1, r, k * 2 + 1, wei, wor, sum); pushup(k); } int main() { ios::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin >> n; long long cnt = 0; for (long long i = 1; i <= n; ++i) { cin >> a; if (a[0] == 'a') { cin >> x; add[++cnt] = x; shu[i] = x; pan[i] = 1; } else if (a[0] == 'd') { cin >> x; shu[i] = x; pan[i] = -1; } } sort(add + 1, add + cnt + 1); long long sum = 1; for (long long i = 1; i <= cnt; ++i) if (id[add[i]] == 0) { id[add[i]] = sum; ++sum; } for (long long i = 1; i <= n; ++i) if (pan[i] == 0) cout << tree[1][3] << endl; else update(1, n, 1, id[shu[i]], pan[i] * shu[i], pan[i]); return 0; }
#include <bits/stdc++.h> using namespace std; struct node_t { int key; node_t *ch[2]; double pri; int cnt; long long sum[5]; bool memed; node_t(const int &k, double p) : key(k), pri(p), memed(false) { ch[0] = ch[1] = 0; cnt = 1; for (int i = 0; i < (int)(5); i++) sum[i] = 0; } }; node_t *rotate(node_t *t, int b) { node_t *s = t->ch[1 - b]; t->ch[1 - b] = s->ch[b]; s->ch[b] = t; s->memed = t->memed = false; return s; } node_t *insert(node_t *t, const int &k, double p) { if (!t) return new node_t(k, p); else if (k == t->key) { t->memed = false; return t; } int b = !(k < t->key); t->ch[b] = insert(t->ch[b], k, p); if (t->pri > t->ch[b]->pri) t = rotate(t, 1 - b); t->memed = false; return t; } node_t *insert(node_t *t, const int &k) { return insert(t, k, rand() / (double)RAND_MAX); } node_t *erase(node_t *t, const int &key) { if (!t) { return NULL; } if (key == t->key) { if (!t->ch[0] && !t->ch[1]) return NULL; t = rotate(t, t->ch[0] ? t->ch[1] ? (t->ch[0]->pri < t->ch[1]->pri) : 1 : 0); t = erase(t, key); } else { int b = !(key < t->key); t->ch[b] = erase(t->ch[b], key); } t->memed = false; return t; } inline int count(node_t *t) { if (!t) return 0; else return t->cnt; } void eval(node_t *t) { if (!t) return; if (!t->memed) { node_t *lch = t->ch[0], *rch = t->ch[1]; eval(lch); eval(rch); int lcnt = count(lch); int rcnt = count(rch); t->cnt = lcnt + 1 + rcnt; for (int i = 0; i < (int)(5); i++) t->sum[i] = 0; if (lch) for (int i = 0; i < (int)(5); i++) t->sum[i] = lch->sum[i]; t->sum[lcnt % 5] += t->key; if (rch) for (int i = 0; i < (int)(5); i++) t->sum[(lcnt + 1 + i) % 5] += rch->sum[i]; t->memed = true; } } pair<node_t *, node_t *> split(node_t *t, int k) { node_t *dmy = insert(t, k, -1.0); return make_pair(dmy->ch[0], dmy->ch[1]); } node_t *merge(node_t *l, node_t *r, int k) { node_t *dmy = new node_t(k, -1.0); dmy->ch[0] = l; dmy->ch[1] = r; return erase(dmy, k); } void print(node_t *t, int d = 0) { if (!t) return; print(t->ch[0], d + 1); printf("%*s%d\n", d, "", t->key); print(t->ch[1], d + 1); } int main() { int Q; scanf("%d", &Q); node_t *root = NULL; for (int q = 0; q < (int)(Q); q++) { char buf[256]; int x; scanf("%s", buf); if (buf[0] == 'a') { scanf("%d", &x); root = insert(root, x); } else if (buf[0] == 'd') { scanf("%d", &x); root = erase(root, x); } else { eval(root); if (!root) puts("0"); else cout << root->sum[2] << endl; } } return 0; }
#include <bits/stdc++.h> using namespace std; int n; vector<int> key; int main() { scanf("%d", &n); char s[10]; int rep; for (int t = 0; t < n; t++) { scanf("%s", s); if (s[0] == 's') { long long ans = 0; for (int i = 2; i < key.size(); i += 5) ans += key[i]; printf("%I64d\n", ans); } else { scanf("%d", &rep); if (s[0] == 'a') key.insert(lower_bound(key.begin(), key.end(), rep), rep); else key.erase(lower_bound(key.begin(), key.end(), rep)); } } return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 1e5 + 233; struct cdd { long long sum[5]; int num; } ch[maxn * 4]; int op[maxn], a[maxn], b[maxn]; void update(int l, int r, int cur, int x) { if (l == r) { if (ch[cur].num == 1) { ch[cur].num = 0; ch[cur].sum[0] = 0; } else { ch[cur].num = 1; ch[cur].sum[0] = b[l]; } return; } int lc = cur << 1, rc = lc | 1, mid = (l + r >> 1); if (x <= mid) update(l, mid, lc, x); else update(mid + 1, r, rc, x); for (int i = 0; i < 5; i++) ch[cur].sum[i] = ch[lc].sum[i] + ch[rc].sum[(i + ch[lc].num) % 5]; ch[cur].num = ch[lc].num + ch[rc].num; return; } int main() { int n, cnt = 0; cin >> n; for (int i = 1; i <= n; i++) { string s; cin >> s; if (s[0] == 'a') { op[i] = 1; cin >> a[i]; b[++cnt] = a[i]; } else if (s[0] == 'd') { op[i] = 2; cin >> a[i]; } else op[i] = 3; } sort(b + 1, b + 1 + cnt); for (int i = 1; i < 4 * maxn; i++) { for (int j = 0; j < 5; j++) ch[i].sum[j] = 0; ch[i].num = 0; } for (int i = 1; i <= n; i++) { if (op[i] == 1) { int k = lower_bound(b + 1, b + 1 + cnt, a[i]) - b; update(1, cnt, 1, k); } else if (op[i] == 2) { int k = lower_bound(b + 1, b + 1 + cnt, a[i]) - b; update(1, cnt, 1, k); } else printf("%I64d\n", ch[1].sum[3]); } }
#include <bits/stdc++.h> using namespace std; const int maxn = 100010; long long sum[5][maxn << 2]; long long cnt[maxn << 2]; struct node { char s[10]; int val; } op[100010]; int b[100010]; int tot; void push_up(int rt) { for (int i = 0; i < 5; i++) { sum[i][rt] = sum[i][rt << 1] + sum[(i + 5 - cnt[rt << 1] % 5) % 5][rt << 1 | 1]; } cnt[rt] = cnt[rt << 1] + cnt[rt << 1 | 1]; } void update(int l, int r, int rt, int pos, int val, int key) { if (l == r) { sum[1][rt] += (long long)(key * (long long)val); cnt[rt] += key; return; } int m = (l + r) >> 1; if (pos <= m) update(l, m, rt << 1, pos, val, key); else update(m + 1, r, rt << 1 | 1, pos, val, key); push_up(rt); } int main() { int n; scanf("%d", &n); tot = 0; for (int i = 1; i <= n; i++) { scanf("%s", op[i].s); if (op[i].s[0] != 's') scanf("%d", &op[i].val); b[tot++] = op[i].val; } sort(b, b + tot); for (int i = 1; i <= n; i++) { if (op[i].s[0] != 's') { int pos = lower_bound(b, b + tot, op[i].val) - b; if (op[i].s[0] == 'a') update(0, tot, 1, pos, op[i].val, 1); else update(0, tot, 1, pos, op[i].val, -1); } else printf("%I64d\n", sum[3][1]); } return 0; }
#include <bits/stdc++.h> using namespace std; #pragma comment(linker, "/stack:16000000") #pragma warning(disable : 4996) const int inf = 1 << 25; const double eps = 1e-9; struct Bucket { const static int SIZE = 512; int elems[SIZE]; long long ps[5]; int size; Bucket() { memset((elems), (0), sizeof(elems)); memset((ps), (0), sizeof(ps)); size = 0, offset = 0; } int offset; void shft(int x) { offset += x; if (offset < 0) offset = 4; if (offset > 4) offset = 0; } void add(int id, int x) { elems[id] = x; recalc(); } void del(int id) { elems[id] = 0; recalc(); } int Size() const { return size; } void recalc() { size = 0; memset((ps), (0), sizeof(ps)); for (int i = 0, j = 0; i < SIZE; ++i) if (elems[i]) { ++size; ps[j % 5] += elems[i]; ++j; } } long long Sum() const { for (int x = 0;; ++x) if ((offset + x) % 5 == 2) return ps[x]; } }; vector<Bucket> buckets; long long sum() { long long ret = 0; for (int i = (0); i < ((int)buckets.size()); ++i) ret += buckets[i].Sum(); return ret; } vector<int> elems; vector<pair<string, int> > queries; int main() { int q; cin >> q; for (int i = (0); i < (q); ++i) { string cmd; cin >> cmd; if (cmd == "sum") queries.push_back(make_pair("sum", 0)); else { int x; cin >> x; queries.push_back(make_pair(cmd, x)); elems.push_back(x); } } sort(elems.begin(), elems.end()); elems.resize(unique(elems.begin(), elems.end()) - elems.begin()); buckets.resize(elems.size() / Bucket::SIZE + 2); for (int i = (0); i < (q); ++i) { string cmd = queries[i].first; int x = queries[i].second; if (cmd == "sum") cout << sum() << endl; else { int id = lower_bound(elems.begin(), elems.end(), x) - elems.begin(); int bid = id / Bucket::SIZE; if (cmd == "add") { buckets[bid].add(id % Bucket::SIZE, x); for (int i = (bid + 1); i < ((int)buckets.size()); ++i) buckets[i].shft(1); } else { buckets[bid].del(id % Bucket::SIZE); for (int i = (bid + 1); i < ((int)buckets.size()); ++i) buckets[i].shft(-1); } } } return 0; }
#include <bits/stdc++.h> using namespace std; char ts[200]; int s[800010]; int tot, b[800010], n, a1, A[800010], B[800010]; long long tr[2100000][6]; void update(int a) { s[a] = s[a * 2] + s[a * 2 + 1]; for (int i = 0; i < 5; i++) tr[a][i] = tr[a * 2][i] + tr[a * 2 + 1][(i - s[a * 2] % 5 + 5) % 5]; } void ins(int l, int r, int p, int q, int now, int ke) { if (p <= l && r <= q) { tr[now][0] = ke; if (ke == 0) s[now] = 0; else s[now] = 1; } else { int mi = (l + r) / 2; if (p < mi) ins(l, mi, p, q, now * 2, ke); if (mi < q) ins(mi, r, p, q, now * 2 + 1, ke); update(now); } } int main() { scanf("%d", &n); tot = 0; for (int i = 0; i < n; i++) { scanf(" %s", &ts); if (ts[0] == 'a') { scanf("%d", &a1); A[i] = 0, B[i] = a1; b[tot++] = a1; } else if (ts[0] == 'd') { scanf("%d", &a1); A[i] = 1, B[i] = a1; b[tot++] = a1; } else A[i] = 2; } sort(b, b + tot); tot = unique(b, b + tot) - b; for (int i = 0; i < n; i++) { if (A[i] == 0) { int a = lower_bound(b, b + tot, B[i]) - b; a++; while (b[a - 1] != B[i]) cout << b[a - 1] << ' ' << B[i] << endl; ins(0, tot, a - 1, a, 1, B[i]); } else if (A[i] == 1) { int a = lower_bound(b, b + tot, B[i]) - b; a++; while (b[a - 1] != B[i]) cout << i << endl; ins(0, tot, a - 1, a, 1, 0); } else printf("%I64d\n", tr[1][2]); } }
#include <bits/stdc++.h> using namespace std; struct Node { int left, right; int cnt; long long sum[5]; } L[100005 * 4]; int n, tot, a[100005], k, q[100005]; char str[100005][10]; void Bulid(int step, int l, int r) { L[step].left = l; L[step].right = r; L[step].cnt = 0; memset(L[step].sum, 0, sizeof(L[step].sum)); if (l == r) return; int m = (l + r) / 2; Bulid((step << 1), l, m); Bulid((step << 1 | 1), m + 1, r); } void Push_Up(int step) { for (int i = 0; i < 5; i++) L[step].sum[i] = (long long)L[(step << 1)].sum[i] + L[(step << 1 | 1)].sum[((i - L[(step << 1)].cnt) % 5 + 5) % 5]; } void Update(int step, int pos, int num) { L[step].cnt += 2 * k - 1; if (L[step].left == L[step].right) { L[step].sum[0] = (long long)k * num; return; } int m = (L[step].left + L[step].right) / 2; if (pos <= m) Update((step << 1), pos, num); else Update((step << 1 | 1), pos, num); Push_Up(step); } int main() { while (scanf("%d", &n) != EOF) { tot = 0; for (int i = 0; i < n; i++) { scanf("%s", str[i]); if (str[i][0] != 's') { scanf("%d", &q[i]); a[tot++] = q[i]; } } sort(a, a + tot); tot = unique(a, a + tot) - a; if (tot == 0) memset(L[1].sum, 0, sizeof(L[1].sum)); else Bulid(1, 1, tot); for (int i = 0; i < n; i++) { int pos = lower_bound(a, a + tot, q[i]) - a; if (str[i][0] == 'a') k = 1, Update(1, pos, q[i]); else if (str[i][0] == 'd') k = 0, Update(1, pos, q[i]); else printf("%I64d\n", L[1].sum[2]); } } return 0; }
#include <bits/stdc++.h> using namespace std; struct node { int cn; long long sm[5]; } tr[(100000 << 3) + 100]; void update(int p, int v, int m, int op, int st, int fn) { if (st == fn) { if (op == 1) { tr[p].sm[0] += v; tr[p].cn++; } else { tr[p].sm[0] -= v; tr[p].cn--; } return; } int md = (st + fn) >> 1, lf = (p << 1) + 1, rt = lf + 1; if (m <= md) update(lf, v, m, op, st, md); else update(rt, v, m, op, md + 1, fn); md = tr[lf].cn % 5; int i; for (i = 0; i < 5; i++) tr[p].sm[i] = tr[lf].sm[i] + tr[rt].sm[(i + md) % 5]; tr[p].cn = tr[p].cn + op; } pair<string, int> qr[100000 + 10]; map<int, int> M; int main() { char wd[10]; int n, i, u, L; cin >> n; for (i = 0; i < n; i++) { scanf("%s", wd); if (wd[0] != 's') { scanf("%d", &u); M[u] = 0; qr[i] = make_pair(string(wd), u); } else qr[i] = make_pair(string(wd), 0); } i = 1; for (map<int, int>::iterator it = M.begin(); it != M.end(); it++) { it->second = i++; } L = i; for (i = 0; i < n; i++) { if (qr[i].first[0] == 's') { printf("%I64d\n", tr[0].sm[3]); } else { update(0, qr[i].second, M[qr[i].second], qr[i].first[0] == 'a' ? 1 : -1, 1, n); } } return 0; }
#include <bits/stdc++.h> using namespace std; long long tmp, cnt, b[200012]; struct data { long long type, x, id; } a[200012]; struct node { long long l, r, w[5], cnt; }; struct segtree { node tr[200012 * 8]; void up(long long rt) { long long i; tr[rt].cnt = tr[rt << 1].cnt + tr[rt << 1 | 1].cnt; for (i = 0; i <= 4; ++i) tr[rt].w[i] = tr[rt << 1].w[i] + tr[rt << 1 | 1].w[((i - tr[rt << 1].cnt) % 5 + 5) % 5]; } void mk(long long rt) { long long l = tr[rt].l, r = tr[rt].r, mid = (tr[rt].l + tr[rt].r) >> 1; if (l == r) return; tr[rt << 1].l = l; tr[rt << 1].r = mid; mk(rt << 1); tr[rt << 1 | 1].l = mid + 1; tr[rt << 1 | 1].r = r; mk(rt << 1 | 1); } void add(long long a, long long b, long long num, long long rt) { long long l = tr[rt].l, r = tr[rt].r, mid = (tr[rt].l + tr[rt].r) >> 1; if (l == r) { tr[rt].w[1] += num * b; tr[rt].cnt += b; return; } if (a <= mid) add(a, b, num, rt << 1); else add(a, b, num, rt << 1 | 1); up(rt); } } tree; map<long long, long long> mp; signed main() { long long i, m, x; char str[8]; scanf("%lld\n", &m); for (i = 1; i <= m; ++i) { scanf("%s ", str); if (str[0] == 'a') { scanf("%lld\n", &x); a[i].type = 1; a[i].x = x; b[++cnt] = x; } else if (str[0] == 'd') { scanf("%lld\n", &x); a[i].type = 2; a[i].x = x; } else a[i].type = 0; } sort(b + 1, b + cnt + 1); for (i = 1; i <= cnt; ++i) if (b[i] != b[i - 1]) mp[b[i]] = ++tmp; for (i = 1; i <= m; ++i) if (a[i].x) a[i].id = mp[a[i].x]; if (cnt == 0) { for (i = 1; i <= m; ++i) printf("0\n"); return 0; } tree.tr[1].l = 1; tree.tr[1].r = cnt; tree.mk(1); for (i = 1; i <= m; ++i) { if (a[i].type == 1) tree.add(a[i].id, 1, a[i].x, 1); else if (a[i].type == 2) tree.add(a[i].id, -1, a[i].x, 1); else printf("%lld\n", tree.tr[1].w[3]); } return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 100010; const int INF = 0x3f3f3f3f; const int iinf = 1 << 30; const long long linf = 2e18; const int MOD = 1000000007; const double eps = 1e-7; void douout(double x) { printf("%lf\n", x + 0.0000000001); } template <class T> void print(T a) { cout << a << endl; exit(0); } template <class T> void chmin(T &a, T b) { if (a > b) a = b; } template <class T> void chmax(T &a, T b) { if (a < b) a = b; } template <class T> void upd(T &a, T b) { (a += b) %= MOD; } template <class T> void mul(T &a, T b) { a = (long long)a * b % MOD; } long long n, x; long long tree[800005][6], add[400005], pan[400005], shu[400005]; long long num[800005]; char a[10]; map<long long, long long> id; inline long long read() { int x = 0, f = 1; char ch = getchar(); while (ch < '0' || ch > '9') { if (ch == '-') f = -1; ch = getchar(); } while (ch >= '0' && ch <= '9') { x = x * 10 + ch - '0'; ch = getchar(); } return x * f; } long long ls(long long k) { return k << 1; } long long rs(long long k) { return k << 1 | 1; } void push_up(long long i) { num[i] = num[ls(i)] + num[rs(i)]; for (long long j = 0; j <= 4; j++) { tree[i][j] = tree[ls(i)][j] + tree[rs(i)][((j - num[ls(i)]) % 5 + 5) % 5]; } } inline void in(long long left, long long right, long long i, long long wei, long long wor, long long sum) { if (left == right) { tree[i][1] += wor; num[i] += sum; return; } else { long long mid = (left + right) / 2; if (wei <= mid) in(left, mid, ls(i), wei, wor, sum); else in(mid + 1, right, rs(i), wei, wor, sum); push_up(i); } } int main() { long long cnt = 0; n = read(); for (long long i = 1; i <= n; i++) { cin >> a; if (a[0] == 'a') { x = read(); add[++cnt] = x; shu[i] = x; pan[i] = 1; } if (a[0] == 'd') { x = read(); shu[i] = x; pan[i] = -1; } } sort(add + 1, add + cnt + 1); long long sum = 1; for (long long i = 1; i <= cnt; i++) { if (id[add[i]] == 0) { id[add[i]] = sum; sum++; } } for (long long i = 1; i <= n; i++) { if (pan[i] == 0) printf("%lld\n", tree[1][3]); else { in(1, n, 1, id[shu[i]], pan[i] * shu[i], pan[i]); } } return 0; }
#include <bits/stdc++.h> using namespace std; vector<int> v; char s[10]; int main() { int n; cin >> n; while (n--) { scanf("%s", s); int x; if (s[0] == 'a' || s[0] == 'd') scanf("%d", &x); if (s[0] == 'a') v.insert(lower_bound(v.begin(), v.end(), x), x); else if (s[0] == 'd') v.erase(lower_bound(v.begin(), v.end(), x)); else { int i = 2; long long int sum = 0; while (i < v.size()) { sum += v[i]; i += 5; } printf("%lld\n", sum); } } }
#include <bits/stdc++.h> using namespace std; int main() { int n; scanf("%d", &n); vector<int> a; a.reserve(n); for (int i = 0; i < n; i++) { string s; cin >> s; if (s == "sum") { long long sum = 0; int sz = a.size(); for (int j = 2; j < sz; j += 5) sum += a[j]; printf("%I64d\n", sum); } else { int x; scanf("%d", &x); if (s == "add") { a.insert(lower_bound(a.begin(), a.end(), x), x); } else { a.erase(lower_bound(a.begin(), a.end(), x)); } } } return 0; }
#include <bits/stdc++.h> using namespace std; struct S { char op[5]; int x, id; } e[100005]; bool cmpval(S a, S b) { if (a.x == b.x) return a.op[0] < b.op[0]; return a.x < b.x; } bool cmpid(S a, S b) { return a.id < b.id; } int n, cnt, val[100005], num[400005]; long long sum[400005][5]; void build(int idx, int s, int e) { if (s != e) { int mid = (s + e) >> 1; build(idx << 1, s, mid); build(idx << 1 | 1, mid + 1, e); } num[idx] = 0; for (int i = 0; i < 5; i++) sum[idx][i] = 0; } void update(int idx, int s, int e, int pos, int flag) { num[idx] += flag; if (s == e) { sum[idx][1] += (long long)val[s] * flag; return; } int mid = (s + e) >> 1; if (pos <= mid) update(idx << 1, s, mid, pos, flag); else update(idx << 1 | 1, mid + 1, e, pos, flag); for (int i = 0; i < 5; i++) sum[idx][i] = sum[idx << 1][i] + sum[idx << 1 | 1][i - num[idx << 1] % 5 >= 0 ? i - num[idx << 1] % 5 : i - num[idx << 1] % 5 + 5]; } long long query(int idx, int s, int e, int mod) { return sum[idx << 1][mod] + sum[idx << 1 | 1] [mod - num[idx << 1] % 5 >= 0 ? mod - num[idx << 1] % 5 : mod - num[idx << 1] % 5 + 5]; } int main() { int i, j; long long ans; while (~scanf("%d", &n)) { map<int, int> mp; for (i = 0; i < n; i++) { scanf("%s", e[i].op); if (e[i].op[0] == 's') e[i].x = 0; else scanf("%d", &e[i].x); e[i].id = i; } sort(e, e + n, cmpval); cnt = 1; for (i = 0; i < n; i++) { if (e[i].op[0] == 'a') { if (!mp[e[i].x]) mp[e[i].x] = cnt++; val[mp[e[i].x]] = e[i].x; e[i].x = mp[e[i].x]; } else if (e[i].op[0] == 'd') { e[i].x = mp[e[i].x]; } } sort(e, e + n, cmpid); cnt--; if (!cnt) { for (i = 0; i < n; i++) { if (e[i].op[0] == 's') { printf("0\n"); } } continue; } build(1, 1, cnt); for (i = 0; i < n; i++) { if (e[i].op[0] == 'a') update(1, 1, cnt, e[i].x, 1); else if (e[i].op[0] == 'd') update(1, 1, cnt, e[i].x, -1); else printf("%I64d\n", query(1, 1, n, 3)); } } }
#include <bits/stdc++.h> using namespace std; const long long maxn = 1e5 + 10; long long a[maxn]; struct treap { treap *lc, *rc; long long val, pri, sum, sz; treap(long long v) : val(v) { lc = rc = nullptr; sz = 1; pri = rand(); sum = v; } void pull() { sz = (lc ? lc->sz : 0) + (rc ? rc->sz : 0) + 1; sum = val + (lc ? lc->sum : 0) + (rc ? rc->sum : 0); } } * tr[5], *another; treap *merge(treap *a, treap *b) { if (!a || !b) return a ? a : b; if (a->pri > b->pri) { a->rc = merge(a->rc, b); a->pull(); return a; } else { b->lc = merge(a, b->lc); b->pull(); return b; } } void split(treap *t, long long k, treap *&a, treap *&b) { if (!t) return (a = nullptr, b = nullptr), void(); if (t->val <= k) { a = t; split(t->rc, k, a->rc, b); a->pull(); } else { b = t; split(t->lc, k, a, b->lc); b->pull(); } } long long get_pos(long long v) { treap *a, *b; split(another, v - 1, a, b); long long ret = (a ? a->sz : 0) + 1; another = merge(a, b); return ret; } vector<treap *> get_suff(long long v) { vector<treap *> ret; for (long long i = 0; i < 5; ++i) { treap *a, *b; split(tr[i], v, a, b); ret.push_back(b); tr[i] = a; } return ret; } void insert(treap *&t, long long v) { treap *a, *b; split(t, v - 1, a, b); t = merge(merge(a, new treap(v)), b); } void erase(treap *&t, long long v) { treap *a, *b, *c, *d; split(t, v - 1, a, b); split(b, v, c, d); t = merge(a, d); } int32_t main() { srand(7122); ios_base::sync_with_stdio(false); cin.tie(0); long long n; cin >> n; while (n--) { string s; cin >> s; if (s == "add") { long long x; cin >> x; long long k = get_pos(x); vector<treap *> suff = get_suff(x); for (long long i = 0; i < 5; ++i) { long long j = (i + 1) % 5; tr[j] = merge(tr[j], suff[i]); } insert(tr[k % 5], x); insert(another, x); } if (s == "del") { long long x; cin >> x; long long k = get_pos(x); vector<treap *> suff = get_suff(x); for (long long i = 0; i < 5; ++i) { long long j = (i - 1 + 5) % 5; tr[j] = merge(tr[j], suff[i]); } erase(tr[k % 5], x); erase(another, x); } if (s == "sum") { cout << (tr[3] ? tr[3]->sum : 0) << '\n'; } } return 0; }
#include <bits/stdc++.h> using namespace std; const int inf = 0x3f3f3f3f, mod = 1000000007; const double pi = 3.1415926535897932, eps = 1e-6; int cnt[262200]; long long sum[262200][5]; void chan(int x) { int i, l = x << 1, r = (x << 1) + 1; cnt[x] = cnt[l] + cnt[r]; for (int(i) = (0); (i) <= (4); (i)++) sum[x][i] = sum[l][i] + sum[r][(i - cnt[l] % 5 + 5) % 5]; } int n, a[100005]; vector<pair<int, int> > v; vector<int> num; int main() { cin >> n; for (int(i) = (1); (i) <= (n); (i)++) { string com; int g; cin >> com; if (com[0] != 's') { cin >> g; } v.push_back(make_pair(com[0] == 's' ? inf : g, com[0])); if (com[0] != 's') num.push_back(g); } sort(num.begin(), num.end()); int s = unique(num.begin(), num.end()) - num.begin(); for (int(i) = (1); (i) <= (n); (i)++) { pair<int, int> now = v[i - 1]; if (now.second == 's') cout << sum[1][2] << endl; else { int typ = now.second == 'a' ? 0 : 1, id = (1 << 17) + (lower_bound(num.begin(), num.begin() + s, now.first) - num.begin()); cnt[id] = 1 - typ; sum[id][0] = (1 - typ) * now.first; for (int j = id >> 1; j; j >>= 1) chan(j); } } return 0; }
#include <bits/stdc++.h> using namespace std; class IO { static const int bufSize = 1 << 18; char inBuf[bufSize], outBuf[bufSize]; char *ip1 = inBuf, *ip2 = inBuf; int goodReadBit = 0, op1 = -1, op2 = bufSize - 1; template <typename T> __inline__ __attribute__((always_inline)) void __RI(T& x) { int ch = gc(), neg = 1; x = 0; for (; !(isdigit(ch) || ch == '-' || ch == EOF); ch = gc()) ; if (ch == EOF) { goodReadBit = 0; return; } if (ch == '-') neg = -1, ch = gc(); for (; isdigit(ch); ch = gc()) x = x * 10 + (ch - 48) * neg; } template <typename T> __inline__ __attribute__((always_inline)) void __RC(T& x) { unsigned char ch; while (isspace(ch = gc())) ; x = ch; } __inline__ __attribute__((always_inline)) void __RS(string& x) { char ch; x.clear(); for (ch = gc(); isspace(ch); ch = gc()) ; if (ch == EOF) { goodReadBit = 0; return; } for (; !isspace(ch); ch = gc()) x.push_back(ch); } public: __inline__ __attribute__((always_inline)) int gc() { return ip1 == ip2 && (ip2 = (ip1 = inBuf) + fread(inBuf, 1, bufSize, stdin), ip1 == ip2) ? EOF : *ip1++; } __inline__ __attribute__((always_inline)) IO& R(char& x) { __RC(x); return (*this); } __inline__ __attribute__((always_inline)) IO& R(unsigned char& x) { __RC(x); return (*this); } __inline__ __attribute__((always_inline)) IO& R(string& x) { __RS(x); return (*this); } template <typename T1, typename T2> __inline__ __attribute__((always_inline)) IO& R(pair<T1, T2>& x) { R(x.first), R(x.second); return (*this); } template <typename T> __inline__ __attribute__((always_inline)) IO& R(vector<T>& x) { for (auto& i : x) R(i); return (*this); } template <typename T, typename... Args> __inline__ __attribute__((always_inline)) IO& RA(T* a, int n) { for (int i = 0; i < n; ++i) R(a[i]); return (*this); } template <typename T, typename... Args> __inline__ __attribute__((always_inline)) IO& R(T& x, Args&... args) { R(x), R(args...); return (*this); } template <typename T, typename... Args> __inline__ __attribute__((always_inline)) IO& RA(T* a, int n, Args... args) { for (int i = 0; i < n; ++i) RA(a[i], args...); return (*this); } template <typename T> __inline__ __attribute__((always_inline)) IO& R(T& x) { static_assert(is_integral<T>::value, "Unsupported types"); if (is_integral<T>::value) __RI(x); return (*this); } private: char space = ' '; template <typename T> __inline__ __attribute__((always_inline)) void __WI(T x) { static char buf[64]; static int len = -1; if (x >= 0) { do { buf[++len] = x % 10 + 48, x /= 10; } while (x); } else { pc('-'); do { buf[++len] = -(x % 10) + 48, x /= 10; } while (x); } while (len >= 0) { pc(buf[len]), --len; } } public: __inline__ __attribute__((always_inline)) void pc(const char& x) { if (op1 == op2) flush(); outBuf[++op1] = x; } __inline__ __attribute__((always_inline)) void flush() { fwrite(outBuf, 1, op1 + 1, stdout), op1 = -1; } __inline__ __attribute__((always_inline)) IO& W(const char& x) { pc(x); return (*this); } __inline__ __attribute__((always_inline)) IO& W(const char* x) { while (*x != '\0') pc(*(x++)); return (*this); } __inline__ __attribute__((always_inline)) IO& W(const string& x) { W(x.c_str()); return (*this); } template <typename T> __inline__ __attribute__((always_inline)) IO& W(const vector<T>& x) { for (auto& i : x) WS(i); WL(); return (*this); } __inline__ __attribute__((always_inline)) IO& WL() { W('\n'); return (*this); } template <typename T1, typename T2> __inline__ __attribute__((always_inline)) IO& W(pair<T1, T2>& x) { WS(x.first), W(x.second); return (*this); } template <typename T> __inline__ __attribute__((always_inline)) IO& WL(const T& x) { W(x), W('\n'); return (*this); } __inline__ __attribute__((always_inline)) IO& WS() { W(' '); return (*this); } template <typename T> __inline__ __attribute__((always_inline)) IO& WS(const T& x) { W(x), W(space); return (*this); } template <typename T> __inline__ __attribute__((always_inline)) IO& WA(T* a, int n) { for (int i = 0; i < n; i++) WS(a[i]); WL(); return (*this); } template <typename T, typename... Args> __inline__ __attribute__((always_inline)) IO& W(const T& x, const Args&... args) { W(x), W(space), W(args...); return (*this); } template <typename... Args> __inline__ __attribute__((always_inline)) IO& WL(const Args&... args) { W(args...), W('\n'); return (*this); } template <typename T, typename... Args> __inline__ __attribute__((always_inline)) IO& WA(T* a, int n, Args... args) { for (int i = 0; i < n; i++) WA(a[i], args...); return (*this); } template <typename T> __inline__ __attribute__((always_inline)) IO& W(const T& x) { static_assert(is_integral<T>::value, "Unsupported types"); if (is_integral<T>::value) __WI(x); return (*this); } template <typename T> __inline__ __attribute__((always_inline)) IO& operator>>(T& x) { R(x); return (*this); } template <typename T> __inline__ __attribute__((always_inline)) IO& operator<<(const T& x) { W(x); return (*this); } IO() {} } io; void EXIT(int code) { io.flush(), exit(code); } const int8_t INFC = 0x3f; const int16_t INFS = 0x3f3f; const int32_t INF = 0x3f3f3f3f; const int64_t INFL = 0x3f3f3f3f3f3f3f3fLL; vector<pair<string, int> > ops; map<int, int> fmap, rmap; struct SegmentTree { struct Node { int64_t sum[5]; int cnt = 0; }; static const int MAXN = 1 << 20; Node data[MAXN]; int N; void init(int n) { N = 1; while (N < n) N <<= 1; } void add(int x) { int k = x + N - 1; data[k].cnt = 1; data[k].sum[0] = rmap[x]; while (k) { k = (k - 1) >> 1; data[k].cnt = data[(k << 1) + 1].cnt + data[(k << 1) + 2].cnt; for (int i = 0; i < 5; i++) data[k].sum[i] = data[(k << 1) + 1].sum[i] + data[(k << 1) + 2].sum[(i - data[(k << 1) + 1].cnt % 5 + 5) % 5]; } } void del(int x) { int k = x + N - 1; data[k].cnt = 0; data[k].sum[0] = 0; while (k) { k = (k - 1) / 2; data[k].cnt = data[(k << 1) + 1].cnt + data[(k << 1) + 2].cnt; for (int i = 0; i < 5; i++) data[k].sum[i] = data[(k << 1) + 1].sum[i] + data[(k << 1) + 2].sum[(i - data[(k << 1) + 1].cnt % 5 + 5) % 5]; } } } segmentTree; int main() { int q; io >> q; ops.resize(q); for (auto& [k, v] : ops) { io >> k; if (k[0] != 's') io >> v, fmap[v] = 1; } segmentTree.init(fmap.size()); int key = 0; for (auto& [k, v] : fmap) key++, v = key, rmap[key] = k; for (auto& [k, v] : ops) if (k[0] != 's') v = fmap[v]; for (auto [k, v] : ops) { if (k[0] == 's') io.WL(segmentTree.data[0].sum[2]); else if (k[0] == 'a') segmentTree.add(v); else if (k[0] == 'd') segmentTree.del(v); } EXIT(0); }
#include <bits/stdc++.h> using namespace std; long long h[100010], dat[100010], s[100010][5]; int n, root, tot, l[100010], r[100010], sum[100010]; inline void update(int x) { if (!x) return; int ss = sum[l[x]] + 1; for (int i = 0; i < 5; i++) s[x][i] = (long long)(s[l[x]][i] + s[r[x]][(i - ss % 5 + 5) % 5]); s[x][ss % 5] += (long long)dat[x]; sum[x] = ss + sum[r[x]]; h[x] = max(h[l[x]], h[r[x]]) + 1; } inline void zig(int &x) { int y = l[x]; l[x] = r[y]; r[y] = x; update(x); update(y); x = y; } inline void zag(int &x) { int y = r[x]; r[x] = l[y]; l[y] = x; update(x); update(y); x = y; } inline void balance(int &x) { update(x); if (h[l[x]] > h[r[x]] + 1) { if (h[l[l[x]]] < h[l[r[x]]]) zag(l[x]); zig(x); } if (h[r[x]] > h[l[x]] + 1) { if (h[r[r[x]]] < h[r[l[x]]]) zig(r[x]); zag(x); } } inline void ins(int &x, long long v) { if (!x) { dat[x = ++tot] = v; l[x] = r[x] = 0; } else ins(v < dat[x] ? l[x] : r[x], v); balance(x); } inline void del(int &x, long long v) { if ((!l[x]) && (!r[x])) { dat[x] = 0; x = 0; return; } if (dat[x] == v) { if (h[l[x]] > h[r[x]]) { zig(x); del(r[x], v); } else { zag(x); del(l[x], v); } } else del(v < dat[x] ? l[x] : r[x], v); balance(x); } int main() { scanf("%d\n", &n); memset(l, 0, sizeof(l)); memset(r, 0, sizeof(r)); memset(s, 0, sizeof(s)); memset(h, 0, sizeof(h)); memset(dat, 0, sizeof(dat)); memset(sum, 0, sizeof(sum)); root = 1; tot = 0; h[0] = -1; while (n--) { char x[10]; scanf("%s", &x); char y = x[0]; long long z; if (y == 'a') { scanf("%I64d", &z); ins(root, z); } else if (y == 'd') { scanf("%I64d", &z); del(root, z); } else printf("%I64d\n", s[root][3]); } return 0; }