text
stringlengths
49
983k
#include <bits/stdc++.h> using namespace std; inline int read() { char ch = getchar(); int nega = 1; while (!isdigit(ch)) { if (ch == '-') nega = -1; ch = getchar(); } int ans = 0; while (isdigit(ch)) { ans = ans * 10 + ch - 48; ch = getchar(); } if (nega == -1) return -ans; return ans; } int add(int x, int y) { return x + y > 998244353 ? x + y - 998244353 : x + y; } int sub(int x, int y) { return x - y < 0 ? x - y + 998244353 : x - y; } vector<int> a[1000005]; vector<int> sum[1000005]; vector<int> res[1000005], r[1000005]; char s[1000005]; int n, m; int get(int x1, int y1, int x2, int y2) { return sum[x2][y2] + sum[x1 - 1][y1 - 1] - sum[x1 - 1][y2] - sum[x2][y1 - 1]; } bool judge(int mid) { for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) res[i][j] = r[i][j] = 0; } mid = mid + mid + 1; for (int i = 1; i + mid - 1 <= n; i++) { for (int j = 1; j + mid - 1 <= m; j++) { int re = get(i, j, i + mid - 1, j + mid - 1); if (re != mid * mid) continue; res[i + mid / 2][j + mid / 2] = 1; r[i][j]++, r[i + mid][j]--, r[i][j + mid]--, r[i + mid][j + mid]++; } } for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { r[i][j] += r[i - 1][j] + r[i][j - 1] - r[i - 1][j - 1]; if (a[i][j] == 1 && r[i][j] == 0) return false; } } return true; } signed main() { cin >> n >> m; for (int i = 0; i <= m; i++) a[0].push_back(0); for (int i = 0; i <= m; i++) sum[0].push_back(0); for (int i = 1; i <= n; i++) { scanf("%s", s + 1); a[i].push_back(0); for (int j = 1; j <= m; j++) a[i].push_back(s[j] == 'X'); } for (int i = 1; i <= n; i++) { sum[i].push_back(0); for (int j = 1; j <= m; j++) { sum[i].push_back(sum[i - 1][j] + sum[i][j - 1] - sum[i - 1][j - 1] + a[i][j]); } } for (int i = 0; i <= n + 1; i++) { for (int j = 0; j <= m + 1; j++) res[i].push_back(0), r[i].push_back(0); } int l = 0, r = n * m, ans; while (l <= r) { int mid = (l + r) / 2; if (judge(mid)) ans = mid, l = mid + 1; else r = mid - 1; } judge(ans); cout << ans << endl; for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { printf("%c", res[i][j] == 1 ? 'X' : '.'); } printf("\n"); } return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = 1 << 29; const int NN = (int)4e6 + 5; int q[NN]; vector<string> grid; int n, m; vector<vector<int> > dist_from_fire; vector<vector<int> > dist; int beg, fin; inline void add(int v) { q[fin++] = v; } inline int pop() { return q[beg++]; } void bfs(vector<vector<int> >& dist) { while (beg < fin) { int x = pop(); int y = pop(); for (int dx = -1; dx <= 1; dx++) { for (int dy = -1; dy <= 1; dy++) if (dx || dy) { int n_x = x + dx; int n_y = y + dy; if (grid[n_x][n_y] == 'X' && dist[n_x][n_y] == INF) { dist[n_x][n_y] = dist[x][y] + 1; add(n_x); add(n_y); } } } } } void bfs_fire(vector<vector<int> >& dist) { while (beg < fin) { int x = pop(); int y = pop(); for (int dx = -1; dx <= 1; dx++) { for (int dy = -1; dy <= 1; dy++) if (dx || dy) { int n_x = x + dx; int n_y = y + dy; if (0 <= n_x && n_x < n && 0 <= n_y && n_y < m && dist[n_x][n_y] == INF) { dist[n_x][n_y] = dist[x][y] + 1; add(n_x); add(n_y); } } } } } bool can(int T) { beg = 0, fin = 0; dist.clear(); dist.resize(n, vector<int>(m, INF)); for (int i = 1; i < n - 1; i++) { for (int j = 1; j < m - 1; j++) { if (grid[i][j] == 'X' && dist_from_fire[i][j] >= T) add(i), add(j), dist[i][j] = 0; } } bfs_fire(dist); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (grid[i][j] == 'X' && dist[i][j] > T) return false; if (grid[i][j] == '.' && dist[i][j] <= T) return false; } } return true; } int main() { ios_base::sync_with_stdio(false); cin >> n >> m; m += 2; n += 2; grid.resize(n, string(m, '.')); for (int i = 0; i < n - 2; i++) { for (int j = 0; j < m - 2; j++) cin >> grid[i + 1][j + 1]; } dist_from_fire.clear(); dist_from_fire.resize(n, vector<int>(m, INF)); beg = 0, fin = 0; for (int x = 0; x < n; x++) for (int y = 0; y < m; y++) { if (grid[x][y] == 'X') { bool ok = false; for (int dx = -1; dx <= 1 && !ok; dx++) { for (int dy = -1; dy <= 1 && !ok; dy++) if (dx || dy) { int n_x = x + dx; int n_y = y + dy; if (grid[n_x][n_y] == '.') ok = true; } } if (ok == true) { add(x); add(y); dist_from_fire[x][y] = 0; } } } bfs(dist_from_fire); int T = -1; for (int x = 0; x < n; x++) { for (int y = 0; y < m; y++) { if (grid[x][y] == 'X') T = max(T, dist_from_fire[x][y]); } } int lo = 0, hi = T + 1; while (lo < hi) { T = (lo + hi + 1) >> 1; if (can(T) == false) { hi = T - 1; } else lo = T; } T = lo; cout << T << endl; for (int i = 1; i < n - 1; i++) { for (int j = 1; j < m - 1; j++) { if (grid[i][j] == 'X' && dist_from_fire[i][j] >= T) cout << 'X'; else cout << '.'; } cout << "\n"; } return 0; }
#include <bits/stdc++.h> using namespace std; const double pi = acos(-1); template <class T> using min_heap = priority_queue<T, vector<T>, greater<T>>; template <class T> using max_heap = priority_queue<T>; const int mod = 998244353; const int inf = 0x3fffffff; const int N = 2 * 1e5 + 10; long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; } struct PairHash { template <typename T1, typename T2> std::size_t operator()(const pair<T1, T2> &p) const { return hash<T1>()(p.first) ^ hash<T2>()(p.second); } }; int n, m; const int d[][2] = {{0, 1}, {1, 0}, {0, -1}, {-1, 0}, {1, 1}, {1, -1}, {-1, 1}, {-1, -1}}; void calc_ng(vector<char *> &ng, const vector<char *> &g, int T, const vector<vector<int>> &sum) { for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { ng[i][j] = '.'; } } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { int zi = i - T * 2; int zj = j - T * 2; if (zi < 0 || zj < 0) continue; int s = sum[i][j] - (zi - 1 >= 0 ? sum[zi - 1][j] : 0) - (zj - 1 >= 0 ? sum[i][zj - 1] : 0) + (zi - 1 >= 0 && zj - 1 >= 0 ? sum[zi - 1][zj - 1] : 0); if (s == (2 * T + 1) * (2 * T + 1)) ng[i - T][j - T] = 'X'; } } } bool verify_ng(vector<char *> &ng, const vector<char *> &g, int T) { queue<pair<int, int>> q; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (ng[i][j] == 'X') q.push(pair<int, int>(i, j)); } } for (int t = 0; t < T; t++) { vector<pair<int, int>> n_e; while (!q.empty()) { pair<int, int> head = q.front(); q.pop(); for (int k = 0; k < 8; k++) { int nx = head.first + d[k][0]; int ny = head.second + d[k][1]; if (nx < 0 || nx >= n || ny < 0 || ny >= m) return false; if (ng[nx][ny] != '.') continue; ng[nx][ny] = 'X'; if (g[nx][ny] == '.') return false; n_e.push_back(pair<int, int>(nx, ny)); } } for (auto &p : n_e) q.push(p); } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (ng[i][j] != g[i][j]) return false; } } return true; } bool okay(int T, const vector<char *> &g, vector<char *> &ng, const vector<vector<int>> &sum) { calc_ng(ng, g, T, sum); return verify_ng(ng, g, T); } void solve(int ncase) { scanf("%d%d", &n, &m); vector<char *> g(n); for (int i = 0; i < n; i++) { g[i] = new char[m + 1]; } for (int i = 0; i < n; i++) { scanf("%s", g[i]); g[i][m] = 0; } int ans = max(n, m); int T = (ans + 1) / 2 - 1; if (T == 0) { printf("%d\n", 0); for (int i = 0; i < n; i++) printf("%s\n", g[i]); return; } vector<vector<int>> col_sum(n, vector<int>(m)); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { col_sum[i][j] = (j > 0 ? col_sum[i][j - 1] : 0) + (g[i][j] == 'X'); } } vector<vector<int>> sum(n, vector<int>(m)); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { sum[i][j] = (i > 0 ? sum[i - 1][j] : 0) + col_sum[i][j]; } } vector<char *> ng(n); for (int i = 0; i < n; i++) { ng[i] = new char[m + 1]; for (int j = 0; j < m; j++) { ng[i][j] = '.'; } ng[i][m] = 0; } int l = 0, r = T + 1; while (l + 1 < r) { int mid = (l + r) / 2; if (okay(mid, g, ng, sum)) l = mid; else r = mid; } printf("%d\n", l); calc_ng(ng, g, l, sum); for (int i = 0; i < n; i++) printf("%s\n", ng[i]); } void solve_all_cases() { int T = 1; int ncase = 0; while (T--) { solve(++ncase); } } int main() { cout << std::fixed; cout << setprecision(9); solve_all_cases(); }
#include <bits/stdc++.h> using namespace std; const int maxn = 1e6 + 1; int linha[] = {-1, -1, -1, 0, 0, 0, 1, 1, 1}; int coluna[] = {-1, 0, 1, -1, 0, 1, -1, 0, 1}; int n, m; unordered_map<int, char> tab[maxn]; unordered_map<int, int> soma[maxn]; unordered_map<int, char> res[maxn]; unordered_map<int, bool> mark[maxn]; int get(int xa, int ya, int xb, int yb) { return (soma[xb][yb] - soma[xb][ya - 1] - soma[xa - 1][yb] + soma[xa - 1][ya - 1]); } void bfs(vector<pair<int, int>> &V, int k) { queue<pair<pair<int, int>, int>> fila; for (auto pp : V) fila.push({pp, 0}); while (!fila.empty()) { int x = fila.front().first.first, y = fila.front().first.second; int d = fila.front().second; fila.pop(); if (d == k) continue; for (int i = 0; i < 9; i++) { int a = x + linha[i], b = y + coluna[i]; if (a < 1 || a > n || b < 1 || b > m || mark[a][b]) continue; mark[a][b] = 1; fila.push({{a, b}, d + 1}); } } } bool ok(int k) { vector<pair<int, int>> V; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) mark[i][j] = 0; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) res[i][j] = '.'; for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { if (i - k < 1 || j - k < 1 || i + k > n || j + k > m) continue; if (get(i - k, j - k, i + k, j + k) == (2 * k + 1) * (2 * k + 1)) { mark[i][j] = 1; V.push_back({i, j}); res[i][j] = 'X'; } } } bfs(V, k); for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) if (tab[i][j] == 'X' && !mark[i][j]) return false; return true; } int main(void) { ios::sync_with_stdio(false); cin.tie(0); cin >> n >> m; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) cin >> tab[i][j]; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) soma[i][j] = soma[i - 1][j] + soma[i][j - 1] - soma[i - 1][j - 1] + (tab[i][j] == 'X'); int ini = 0, fim = 1000001, ans = 0; while (ini <= fim) { int mid = (ini + fim) >> 1; if (ok(mid)) ans = mid, ini = mid + 1; else fim = mid - 1; } cout << ans << "\n"; ok(ans); for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) cout << res[i][j]; cout << "\n"; } }
#include <bits/stdc++.h> using namespace std; const int MOD = 1e9 + 7; int n, m; vector<string> gr; struct Pt { int i, j; Pt(int _i, int _j) : i(_i), j(_j) {} }; bool isValid(Pt p) { return 0 <= p.i && p.i < n && 0 <= p.j && p.j < m; } vector<Pt> dirs = {Pt(-1, 0), Pt(1, 0), Pt(0, -1), Pt(0, 1), Pt(1, 1), Pt(1, -1), Pt(-1, 1), Pt(-1, -1)}; vector<Pt> getNei(Pt p) { vector<Pt> ans; for (auto pd : dirs) { Pt p2(p.i + pd.i, p.j + pd.j); if (isValid(p2)) ans.push_back(p2); } return ans; } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cin >> n >> m; gr.resize(n); for (auto& s : gr) cin >> s; vector<vector<int>> dist(n, vector<int>(m, MOD)); queue<Pt> q; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (gr[i][j] == '.') { dist[i][j] = 0; q.push(Pt(i, j)); } } } while (q.size()) { auto cur = q.front(); q.pop(); for (auto p : getNei(cur)) { if (dist[p.i][p.j] == MOD) { dist[p.i][p.j] = dist[cur.i][cur.j] + 1; q.push(p); } } } for (int i = 0; i < n; i++) { if (gr[i][0] == 'X' && dist[i][0] > 1) { dist[i][0] = 1; q.push(Pt(i, 0)); } if (gr[i][m - 1] == 'X' && dist[i][m - 1] > 1) { dist[i][m - 1] = 1; q.push(Pt(i, m - 1)); } } for (int j = 0; j < m; j++) { if (gr[0][j] == 'X' && dist[0][j] > 1) { dist[0][j] = 1; q.push(Pt(0, j)); } if (gr[n - 1][j] == 'X' && dist[n - 1][j] > 1) { dist[n - 1][j] = 1; q.push(Pt(n - 1, j)); } } while (q.size()) { auto cur = q.front(); q.pop(); for (auto p : getNei(cur)) { if (dist[p.i][p.j] > dist[cur.i][cur.j] + 1) { dist[p.i][p.j] = dist[cur.i][cur.j] + 1; q.push(p); } } } int r = 0; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { r = max(r, dist[i][j]); } } int l = 0; while (l < r) { int mid = (l + r) / 2; vector<vector<int>> d2(n, vector<int>(m, MOD)); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (dist[i][j] >= mid + 1) { q.push(Pt(i, j)); d2[i][j] = 0; } } } while (q.size()) { auto cur = q.front(); q.pop(); for (int i = -1; i <= 1; i++) { for (int j = -1; j <= 1; j++) { if (!i && !j) continue; Pt p(cur.i + i, cur.j + j); if (isValid(p) && d2[p.i][p.j] == MOD) { d2[p.i][p.j] = d2[cur.i][cur.j] + 1; q.push(p); } } } } bool works = 1; for (int i = 0; i < n && works; i++) { for (int j = 0; j < m && works; j++) { if (gr[i][j] == 'X' && d2[i][j] > mid || gr[i][j] == '.' && d2[i][j] <= mid) works = 0; } } if (works) l = mid + 1; else r = mid; } cout << l - 1 << '\n'; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { cout << (dist[i][j] >= l ? 'X' : '.'); } cout << '\n'; } return 0; }
#include <bits/stdc++.h> using namespace std; int n, m; int get(vector<vector<int> > &p, int l, int i, int j) { return 0; } int main() { ios::sync_with_stdio(0); cin.tie(0); cin >> n >> m; char s[n][m]; int x[] = {1, 1, 1, 0, 0, -1, -1, -1}; int y[] = {1, -1, 0, 1, -1, -1, 0, 1}; int a[n + 2][m + 2], b[n + 2][m + 2]; int pref[n + 2][m + 2]; for (int i = 0; i <= n + 1; i++) for (int j = 0; j <= m + 1; j++) { a[i][j] = 0; b[i][j] = 0; } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) cin >> s[i][j]; for (int j = 0; j < m; j++) if (s[i][j] == '.') a[i + 1][j + 1] = 0; else a[i + 1][j + 1] = 1; } int dp[n + 2][m + 2], dp1[n + 2][m + 2], dp2[n + 2][m + 2], dp3[n + 2][m + 2], dp4[n + 2][m + 2]; for (int i = 0; i <= n + 1; i++) for (int j = 0; j <= m + 1; j++) { dp[i][j] = 0; dp1[i][j] = 0; dp2[i][j] = 0; dp3[i][j] = 0; dp4[i][j] = 0; pref[i][j] = 0; } for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) if (a[i][j] == 1) dp1[i][j] = min(min(dp1[i - 1][j] + 1, dp1[i][j - 1] + 1), dp1[i - 1][j - 1] + 1); for (int i = n; i > 0; i--) for (int j = m; j > 0; j--) if (a[i][j] == 1) dp2[i][j] = min(min(dp2[i + 1][j] + 1, dp2[i][j + 1] + 1), dp2[i + 1][j + 1] + 1); for (int i = 1; i <= n; i++) for (int j = m; j > 0; j--) if (a[i][j] == 1) dp3[i][j] = min(min(dp3[i - 1][j] + 1, dp3[i][j + 1] + 1), dp3[i - 1][j + 1] + 1); for (int i = n; i > 0; i--) for (int j = 1; j <= m; j++) if (a[i][j] == 1) dp4[i][j] = min(min(dp4[i + 1][j] + 1, dp4[i][j - 1] + 1), dp4[i + 1][j - 1] + 1); for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) dp[i][j] = min(dp1[i][j], min(dp2[i][j], min(dp3[i][j], dp4[i][j]))); int l = 0, r = (min(n, m) - 1) / 2, mid; while (l < r) { mid = (l + r + 1) / 2; for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { if (dp[i][j] > mid) b[i][j] = 1; else b[i][j] = 0; pref[i][j] = 0; } } int o = 1; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) { if (b[i][j] == 1) pref[i][j] = 1; pref[i][j] += pref[i][j - 1]; } for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) pref[i][j] += pref[i - 1][j]; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) { int k1 = 1, k2 = 1, k3 = 1, k4 = 1; if (a[i][j] == 1) if (pref[i][j] - pref[max(0, i - mid - 1)][j] - pref[i][max(0, j - mid - 1)] + pref[max(0, i - mid - 1)][max(0, j - mid - 1)] == 0) k1 = 0; if (a[i][j] == 1) if (pref[i][min(m, j + mid)] - pref[max(0, i - mid - 1)][min(m, j + mid)] - pref[i][j - 1] + pref[max(0, i - mid - 1)][j - 1] == 0) k2 = 0; if (a[i][j] == 1) if (pref[min(n, i + mid)][j] - pref[i - 1][j] - pref[min(n, i + mid)][max(0, j - mid - 1)] + pref[i - 1][max(0, j - mid - 1)] == 0) k3 = 0; if (a[i][j] == 1) if (pref[min(n, i + mid)][min(m, j + mid)] - pref[i - 1][min(m, j + mid)] - pref[min(n, i + mid)][j - 1] + pref[i - 1][j - 1] == 0) k4 = 0; if (a[i][j] == 0) if (pref[i][j] - pref[max(0, i - mid - 1)][j] - pref[i][max(0, j - mid - 1)] + pref[max(0, i - mid - 1)][max(0, j - mid - 1)] > 0) o = 0; if (a[i][j] == 0) if (pref[i][min(m, j + mid)] - pref[max(0, i - mid - 1)][min(m, j + mid)] - pref[i][j - 1] + pref[max(0, i - mid - 1)][j - 1] > 0) o = 0; if (a[i][j] == 0) if (pref[min(n, i + mid)][j] - pref[i - 1][j] - pref[min(n, i + mid)][max(0, j - mid - 1)] + pref[i - 1][max(0, j - mid - 1)] > 0) o = 0; if (a[i][j] == 0) if (pref[min(n, i + mid)][min(m, j + mid)] - pref[i - 1][min(m, j + mid)] - pref[min(n, i + mid)][j - 1] + pref[i - 1][j - 1] > 0) o = 0; if (k1 + k2 + k3 + k4 == 0) o = 0; } if (o == 1) l = mid; else r = mid - 1; } cout << l << "\n"; for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) if (dp[i][j] > l) cout << 'X'; else cout << '.'; cout << "\n"; } }
#include <bits/stdc++.h> using namespace std; int pre[10000001]; int s[10000001]; int ans[10000001]; int tot[10000001]; int n, m; int Find(int x, int y) { if (x < 0 || y < 0 || x >= n || y >= m) return -1; return x * m + y; } int Query(int x, int y, int a[]) { if (Find(x, y) == -1) return 0; else return a[Find(x, y)]; } bool Check(int x) { x = x * 2 + 1; memset(ans, 0, sizeof(ans)); memset(tot, 0, sizeof(tot)); for (int i = 0; x + i - 1 < n; i++) for (int j = 0; x + j - 1 < m; j++) { int now = Query(i + x - 1, j + x - 1, pre) + Query(i - 1, j - 1, pre) - Query(i + x - 1, j - 1, pre) - Query(i - 1, j + x - 1, pre); if (now == x * x) ans[Find(i, j)] = 1; } for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) tot[Find(i, j)] = ans[Find(i, j)] + Query(i - 1, j, tot) + Query(i, j - 1, tot) - Query(i - 1, j - 1, tot); for (int i = 0; i < n; i++) for (int j = 0; j <= m; j++) if (s[Find(i, j)]) { int t = tot[Find(i, j)] - Query(i - x, j, tot) - Query(i, j - x, tot) + Query(i - x, j - x, tot); if (t == 0) return false; } return true; } int main() { ios::sync_with_stdio(false); cin >> n >> m; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) { char c; cin >> c; if (c == 'X') s[Find(i, j)] = 1; else s[Find(i, j)] = 0; } for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) pre[Find(i, j)] = Query(i - 1, j, pre) + Query(i, j - 1, pre) - Query(i - 1, j - 1, pre) + s[Find(i, j)]; int an = 0, l = 0, r = min(n, m); while (r >= l) { int m = (l + r) / 2; if (Check(m)) { l = m + 1; an = m; } else r = m - 1; } Check(an); cout << an << endl; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) if (i - an >= 0 && j - an >= 0 && ans[Find(i - an, j - an)]) cout << 'X'; else cout << '.'; cout << endl; } }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 11; char a[N]; int s[N]; int n, m; int t[N]; int num(int l, int r) { if (l < 1 || r < 1) return 0; return (l - 1) * m + r; } int sum(int l1, int r1, int l2, int r2) { l1 = max(l1, 1); r1 = max(r1, 1); return s[num(l2, r2)] - s[num(l1 - 1, r2)] - s[num(l2, r1 - 1)] + s[num(l1 - 1, r1 - 1)]; } int sum2(int l1, int r1, int l2, int r2) { l1 = max(l1, 1); r1 = max(r1, 1); return t[num(l2, r2)] - t[num(l1 - 1, r2)] - t[num(l2, r1 - 1)] + t[num(l1 - 1, r1 - 1)]; } bool good(int l1, int r1, int l2, int r2) { if (l1 < 1 || r1 < 1 || l2 > n || r2 > m) return false; int c = sum(l1, r1, l2, r2); if (c == (l2 - l1 + 1) * (r2 - r1 + 1)) return true; return false; } bool good(int x) { x *= 2; x++; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) { int c = 0; if (good(i, j, i + x - 1, j + x - 1)) c = 1; t[num(i, j)] = t[num(i - 1, j)] + t[num(i, j - 1)] - t[num(i - 1, j - 1)] + c; } for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) if (a[num(i, j)] == 1) { if (sum2(i - x + 1, j - x + 1, i, j) == 0) return false; } return true; } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n >> m; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) { char c; cin >> c; if (c == 'X') a[num(i, j)] = 1; s[num(i, j)] = s[num(i - 1, j)] + s[num(i, j - 1)] - s[num(i - 1, j - 1)] + a[num(i, j)]; } int l = 0, r = min(n, m); while (r - l > 1) { int mid = (l + r) / 2; if (good(mid)) l = mid; else r = mid; } int x = 0; if (good(r)) x = r; else x = l; cout << x << "\n"; for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) if (good(i - x, j - x, i + x, j + x)) cout << "X"; else cout << "."; cout << "\n"; } }
#include <bits/stdc++.h> using namespace std; long long n, m; vector<string> a; vector<vector<long long>> pr; vector<pair<long long, long long>> nxt{{1, 0}, {1, 1}, {1, -1}, {-1, 0}, {-1, 1}, {-1, -1}, {0, -1}, {0, 1}}; bool check(long long time) { queue<pair<long long, long long>> q; vector<vector<long long>> mn(n, vector<long long>(m, 1e9)); long long k = (time + time + 1); k = k * k; for (long long i = 0; i < n; i++) { for (long long j = 0; j < m; j++) { if (i - time < 0 || j - time < 0 || i + time >= n || j + time >= m) continue; if (pr[i + time + 1][j + time + 1] + pr[i - time][j - time] - pr[i + time + 1][j - time] - pr[i - time][j + time + 1] != k) continue; else { q.push({i, j}); mn[i][j] = 0; } } } while (!q.empty()) { auto first = q.front(); q.pop(); for (auto j : nxt) { if (first.first + j.first >= n || first.first + j.first < 0 || first.second + j.second >= m || first.second + j.second < 0) continue; if (mn[first.first + j.first][first.second + j.second] != 1e9) continue; mn[first.first + j.first][first.second + j.second] = mn[first.first][first.second] + 1; q.push({first.first + j.first, first.second + j.second}); } } for (long long i = 0; i < n; i++) { for (long long j = 0; j < m; j++) { if ((a[i][j] == '.' && mn[i][j] <= time) || (a[i][j] == 'X' && mn[i][j] > time)) return false; } } return true; } int32_t main() { cin.tie(NULL); cout.tie(NULL); ios::sync_with_stdio(false); cin >> n >> m; a.resize(n); for (long long i = 0; i < n; i++) cin >> a[i]; pr.resize(n + 1, vector<long long>(m + 1, 0)); for (long long i = 0; i < n; i++) { for (long long j = 0; j < m; j++) { pr[i + 1][j + 1] = pr[i + 1][j] + pr[i][j + 1] - pr[i][j] + (a[i][j] == 'X' ? 1 : 0); } } long long l = 0, r = min(n, m) + 1, mid; while (r - l > 1) { mid = (r + l) / 2; if (check(mid)) l = mid; else r = mid; } long long time = l; cout << time << '\n'; long long k = (time + time + 1); k = k * k; for (long long i = 0; i < n; i++) { for (long long j = 0; j < m; j++) { if (i - time < 0 || j - time < 0 || i + time >= n || j + time >= m) { cout << '.'; continue; } if (pr[i + time + 1][j + time + 1] + pr[i - time][j - time] - pr[i + time + 1][j - time] - pr[i - time][j + time + 1] != k) cout << '.'; else cout << 'X'; } cout << '\n'; } return 0; }
#include <bits/stdc++.h> using namespace std; using ll = long long; using vi = vector<int>; using vb = vector<bool>; using vvi = vector<vector<int>>; using vll = vector<long long>; using vpi = vector<pair<int, int>>; using pii = pair<int, int>; const char nl = '\n'; string to_string(char c) { return string(1, c); } string to_string(const char* s) { return (string)s; } string to_string(string s) { return s; } string to_string(bool b) { return b ? "true" : "false"; } string to_string(vector<bool> v) { string res = "{"; for (int i = 0; i < ((int)v.size()); ++i) res += char('0' + v[i]); res += "}"; return res; } template <size_t SZ> string to_string(bitset<SZ> b) { string res = ""; for (int i = 0; i < (SZ); ++i) res += char('0' + b[i]); return res; } template <class A, class B> string to_string(pair<A, B> p); template <class T> string to_string(T& v) { bool fst = 1; string res = "{"; for (const auto& x : v) { if (!fst) res += ", "; fst = 0; res += to_string(x); } res += "}"; return res; } template <class A, class B> string to_string(pair<A, B> p) { return "(" + to_string(p.first) + ", " + to_string(p.second) + ")"; } void DBG() { cerr << "]" << endl; } template <class H, class... T> void DBG(H h, T... t) { cerr << to_string(h); if (sizeof...(t)) cerr << ", "; DBG(t...); } int main() { ios::sync_with_stdio(false); cin.tie(NULL); int n, m; cin >> n >> m; vector<string> mp(n); for (int i = 0; i < n; i++) { cin >> mp[i]; } vector<vector<int>> pre(n + 1, vector<int>(m + 1)); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { pre[i + 1][j + 1] = pre[i + 1][j] + pre[i][j + 1] - pre[i][j] + (mp[i][j] == 'X'); } } auto query = [&](int r0, int c0, int r1, int c1) -> int { if (r0 > r1) swap(r0, r1); if (c0 > c1) swap(c0, c1); return pre[r1][c1] - pre[r1][c0 - 1] - pre[r0 - 1][c1] + pre[r0 - 1][c0 - 1]; }; auto ok = [&](int T) -> bool { vector<vector<int>> dist(n, vector<int>(m, 2e9)); queue<array<int, 2>> q; for (int i = 0; i < n - T + 1; i++) { for (int j = 0; j < m - T + 1; j++) { int count = query(i + 1, j + 1, i + T, j + T); if (count == T * T) { dist[i + (T - 1) / 2][j + (T - 1) / 2] = 0; q.push({i + (T - 1) / 2, j + (T - 1) / 2}); } } } const int D[8][2] = {{1, 0}, {0, -1}, {-1, 0}, {0, 1}, {1, 1}, {1, -1}, {-1, -1}, {-1, 1}}; while (!q.empty()) { auto [i, j] = q.front(); q.pop(); for (int k = 0; k < 8; k++) { int u = i + D[k][0]; int v = j + D[k][1]; if (u >= 0 && u < n && v >= 0 && v < m && dist[i][j] + 1 < dist[u][v]) { dist[u][v] = dist[i][j] + 1; q.push({u, v}); } } } for (int i = 0; i < n; i++) { 0; } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { bool has = dist[i][j] <= (T - 1) / 2; if ((!has && mp[i][j] == 'X') || (has && mp[i][j] == '.')) { return false; } } } return true; }; int low = 0, high = min(n, m) / 2; while (low < high) { int mid = low + (high - low + 1) / 2; bool res = ok(2 * mid + 1); 0; if (res) { low = mid; } else { high = mid - 1; } } int T = low * 2 + 1; cout << ((T - 1) / 2) << nl; vector<string> source(n, string(m, '.')); for (int i = 0; i < n - T + 1; i++) { for (int j = 0; j < m - T + 1; j++) { int count = query(i + 1, j + 1, i + T, j + T); if (count == T * T) { source[i + (T - 1) / 2][j + (T - 1) / 2] = 'X'; } } } for (int i = 0; i < n; i++) { cout << source[i] << nl; } return 0; }
#include <bits/stdc++.h> using namespace std; using ull = unsigned long long; using ll = long long; const int N = 2005; int n, m; vector<vector<char>> a; vector<vector<int>> c, u; bool check2(int i, int j, int i1, int j2) { if (i < 1 || j < 1 || i1 < 1 || j2 < 1) return 0; if (i > n || j > m || i1 > n || j2 > m) return 0; return c[i1][j2] - c[i - 1][j2] - c[i1][j - 1] + c[i - 1][j - 1] == (i1 - i + 1) * (j2 - j + 1); } bool check(int vl) { for (int i = 0; i < n + 2; ++i) { for (int j = 0; j < m + 2; ++j) { u[i][j] = 0; } } for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) { if (a[i][j] == 'X' && check2(i - vl, j - vl, i + vl, j + vl)) { ++u[i - vl][j - vl]; --u[i - vl][j + vl + 1]; --u[i + vl + 1][j - vl]; ++u[i + vl + 1][j + vl + 1]; } } } for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) { u[i][j] += u[i - 1][j] + u[i][j - 1] - u[i - 1][j - 1]; if (a[i][j] == 'X' && u[i][j] == 0) { return 0; } if (a[i][j] == '.' && u[i][j] != 0) { abort(); } } } return 1; } int main() { ios_base::sync_with_stdio(false); cin.tie(0), cout.tie(0); cin >> n >> m; a.resize(n + 2, vector<char>(m + 2, 0)); c.resize(n + 2, vector<int>(m + 2, 0)); u.resize(n + 2, vector<int>(m + 2, 0)); for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) { cin >> a[i][j]; } } for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) { c[i][j] = c[i - 1][j] + c[i][j - 1] - c[i - 1][j - 1] + (a[i][j] == 'X'); } } int l = 0, r = max(n, m), mid; while (r - l > 1) { mid = (l + r) >> 1; if (check(mid)) { l = mid; } else { r = mid; } } cout << l << '\n'; for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) { if (a[i][j] == 'X' && check2(i - l, j - l, i + l, j + l)) { cout << 'X'; } else { cout << '.'; } } cout << '\n'; } return 0; }
#include <bits/stdc++.h> using namespace std; namespace star { const int maxn = 1e6 + 5; int n, m; vector<int> sum[maxn], tot[maxn]; vector<bool> ans[maxn]; char ch[maxn]; bool check(int x) { for (int i = 0; i <= n; i++) { for (int j = 0; j <= m; j++) { tot[i][j] = 0; } } for (int i = x + 1; i <= n - x; i++) { for (int j = x + 1; j <= m - x; j++) { if (sum[i + x][j + x] - sum[i - x - 1][j + x] - sum[i + x][j - x - 1] + sum[i - x - 1][j - x - 1] == (2 * x + 1) * (2 * x + 1)) { tot[i + x + 1][j + x + 1] += 1; tot[i - x][j + x + 1] += -1; tot[i + x + 1][j - x] += -1; tot[i - x][j - x] += 1; } } } int cnt = 0; for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { if (tot[i][j] += tot[i - 1][j] + tot[i][j - 1] - tot[i - 1][j - 1]) { cnt++; } } } return cnt == sum[n][m]; } void work() { scanf("%d%d", &n, &m); for (int i = 0; i <= n + 1; i++) { for (int j = 0; j <= m + 1; j++) { sum[i].push_back(0); tot[i].push_back(0); ans[i].push_back(false); } } char c = getchar(); for (int i = 1; i <= n; i++) { while (c != '.' and c != 'X') c = getchar(); for (int j = 1; j <= m; j++) sum[i][j] = (c == 'X') + sum[i - 1][j] + sum[i][j - 1] - sum[i - 1][j - 1], c = getchar(); } int mid, l = 0, r = (min(n, m) - 1) / 2, res; while (l <= r) { mid = (l + r) >> 1; if (check(mid)) { res = mid; l = mid + 1; } else r = mid - 1; } printf("%d\n", res); for (int i = res + 1; i <= n - res; i++) { for (int j = res + 1; j <= m - res; j++) { if (sum[i + res][j + res] - sum[i - res - 1][j + res] - sum[i + res][j - res - 1] + sum[i - res - 1][j - res - 1] == (2 * res + 1) * (2 * res + 1)) { ans[i][j] = true; } } } for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { putchar((ans[i][j] ? 'X' : '.')); } puts(" "); } } } // namespace star int main() { star::work(); return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = 1e9 + 239; vector<int> dx = {0, 0, 1, -1, 1, 1, -1, -1}; vector<int> dy = {-1, 1, 0, 0, 1, -1, 1, -1}; int n, m; vector<vector<int>> a; vector<vector<int>> ps; vector<vector<int>> cand; vector<vector<int>> d; int gt(int i, int j) { if (i == -1 || j == -1) { return 0; } else { return ps[i][j]; } } void init() { ps.resize(n, vector<int>(m)); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { ps[i][j] = a[i][j] + gt(i, j - 1) + gt(i - 1, j) - gt(i - 1, j - 1); } } } int sm(int i, int j, int m) { return gt(i + m - 1, j + m - 1) - gt(i - 1, j + m - 1) - gt(i + m - 1, j - 1) + gt(i - 1, j - 1); } bool bfs(int x) { queue<pair<int, int>> q; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (cand[i][j]) { d[i][j] = 0; q.push({i, j}); } } } while (!q.empty()) { int i, j; tie(i, j) = q.front(); q.pop(); for (int k = 0; k < 8; k++) { int ni = i + dx[k]; int nj = j + dy[k]; if (ni >= 0 && ni < n && nj >= 0 && nj < m && d[ni][nj] > d[i][j] + 1) { d[ni][nj] = d[i][j] + 1; q.push({ni, nj}); } } } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (a[i][j] && d[i][j] > x) { return false; } } } return true; } bool can(int x) { for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { cand[i][j] = 0; d[i][j] = INF; } } int len = 2 * x + 1; for (int i = 0; i + len <= n; i++) { for (int j = 0; j + len <= m; j++) { if (sm(i, j, len) == len * len) { cand[i + len / 2][j + len / 2] = 1; } } } return bfs(x); } signed main() { ios_base::sync_with_stdio(false); cin.tie(0); cin >> n >> m; a.resize(n, vector<int>(m)); cand.resize(n, vector<int>(m, 0)); d.resize(n, vector<int>(m, INF)); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { char c; cin >> c; a[i][j] = (c == 'X'); } } init(); int l = 0; int r = 507; while (r - l > 1) { int x = (r + l) >> 1; if (can(x)) { l = x; } else { r = x; } } assert(can(l)); cout << l << endl; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (cand[i][j]) cout << 'X'; else cout << '.'; } cout << '\n'; } }
#include <bits/stdc++.h> #pragma GCC target("avx2") #pragma GCC optimization("O3") #pragma GCC optimization("unroll-loops") using namespace std; int fx[4] = {0, 1, 0, -1}; int fy[4] = {1, 0, -1, 0}; const long long M = 2e5 + 10, M2 = 1e6 + 10, oo = 1e9 + 7; const long long MC = (1 << 22) + 5; vector<string> vs, setfire; int n, m; void getpre(int id, vector<vector<int> > &pre) { pre = vector<vector<int> >(n + 2, vector<int>(m + 2, 0)); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (id == 0 && vs[i][j] == 'X') pre[i][j]++; if (id == 1 && setfire[i][j] == 'X') pre[i][j]++; if (i > 0) pre[i][j] += pre[i - 1][j]; if (j > 0) pre[i][j] += pre[i][j - 1]; if (i > 0 && j > 0) pre[i][j] -= pre[i - 1][j - 1]; } } } int getsum(int lx, int ly, int rx, int ry, vector<vector<int> > &pre) { if (lx < 0 || lx >= n || ly < 0 || ly >= m || rx < 0 || rx >= n || ry < 0 || ry >= m) return 0; int ret = pre[rx][ry]; if (lx > 0) ret -= pre[lx - 1][ry]; if (ly > 0) ret -= pre[rx][ly - 1]; if (lx > 0 && ly > 0) ret += pre[lx - 1][ly - 1]; return ret; } int iscenter(int x, int y, int t, vector<vector<int> > &pre) { int lx = x - t, ly = y - t, rx = x + t, ry = y + t; if (getsum(lx, ly, rx, ry, pre) == (2 * t + 1) * (2 * t + 1)) return 1; return 0; } int iscell(int x, int y, int t, vector<vector<int> > &cenpre) { if (vs[x][y] == '.') return 1; int lx = max(0, x - t), ly = max(0, y - t), rx = min(n - 1, x + t), ry = min(m - 1, y + t); int ret = getsum(lx, ly, rx, ry, cenpre); return (ret > 0); } void precomp() {} void solve() { cin >> n >> m; vector<vector<int> > pre, cenpre; string s; for (int i = 0; i < n; i++) { cin >> s; vs.push_back(s); } getpre(0, pre); setfire = vector<string>(n + 2, string(m + 2, '.')); auto can = [&](int tm) { for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (iscenter(i, j, tm, pre)) { setfire[i][j] = 'X'; } else setfire[i][j] = '.'; } } getpre(1, cenpre); int ret = 1; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { ret &= (iscell(i, j, tm, cenpre)); } } return ret; }; int lo = 0, hi = min(n, m); while (lo < hi) { int mid = (lo + hi) / 2; if (can(mid)) lo = mid + 1; else hi = mid; } cout << lo - 1 << '\n'; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (iscenter(i, j, lo - 1, pre)) cout << "X"; else cout << "."; } cout << '\n'; } } int32_t main() { ios_base::sync_with_stdio(false); cin.tie(NULL); precomp(); solve(); return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 5000005; char p[maxn]; int a[maxn], b[maxn], c[maxn]; int n, m; int ad(int i, int j) { return (i - 1) * m + j; } int main() { scanf("%d%d", &n, &m); for (int i = 1; i <= n; i++) scanf("%s", p + ad(i, 1)); for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) { if (p[ad(i, j)] == '.') a[ad(i, j)] = 0; else if (i == 1 || j == 1) a[ad(i, j)] = 1; else a[ad(i, j)] = min(a[ad(i - 1, j - 1)], min(a[ad(i - 1, j)], a[ad(i, j - 1)])) + 1; } int l = 0, r = 1000000; int mid, x; while (r > l + 1) { mid = (l + r) >> 1; x = 2 * mid + 1; bool flag = true; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) if (a[ad(i, j)] >= x) c[ad(i, j)] = x; else c[ad(i, j)] = 0; for (int i = n; i >= 1; i--) for (int j = m; j >= 1; j--) { if (i > 1) c[ad(i - 1, j)] = max(c[ad(i - 1, j)], c[ad(i, j)] - 1); if (j > 1) c[ad(i, j - 1)] = max(c[ad(i, j - 1)], c[ad(i, j)] - 1); if (i > 1 && j > 1) c[ad(i - 1, j - 1)] = max(c[ad(i - 1, j - 1)], c[ad(i, j)] - 1); } for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) { if (a[ad(i, j)] == 0) continue; if (c[ad(i, j)] == 0) flag = false; } if (flag) l = mid; else r = mid; } printf("%d\n", l); x = 2 * l + 1; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) b[ad(i, j)] = '.'; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) if (a[ad(i, j)] >= x) b[ad(i - l, j - l)] = 'X'; for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) printf("%c", b[ad(i, j)]); puts(""); } return 0; }
#include <bits/stdc++.h> #pragma GCC optimize("Ofast") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") using namespace std; long long N = 1234567891, M = 31; long long n, m, t, k, f, mi = 2e9, x, y, z, ma, x3, x2, y2, l, r, i, j, ans, vv; char c[1010000]; string s; vector<long long> v, v2, v3; vector<long long> a[1100000], b[1100000], d, d2, dp[1100000]; int main() { scanf("%d%d", &n, &m); for (i = 1; i <= n; i++) { scanf("%s", c); s = c; a[i].push_back(0); for (j = 1; j <= m; j++) { a[i].push_back((s[j - 1] == 'X')); } } for (i = 0; i <= n + 1; i++) for (j = 0; j <= m + 1; j++) { b[i].push_back(0); dp[i].push_back(0); } for (i = 1; i <= n; i++) { for (j = 1; j <= m; j++) { b[i][j] = a[i][j] + b[i - 1][j] + b[i][j - 1] - b[i - 1][j - 1]; } } long long l = 0, r = min((n - 1) / 2, (m - 1) / 2) + 1; while (r - l > 1) { int t2 = (l + r) / 2; int t = t2 * 2 + 1; for (i = 0; i <= n + 1; i++) { for (j = 0; j <= m + 1; j++) { dp[i][j] = 0; } } for (i = t; i <= n; i++) { for (j = t; j <= m; j++) { if (b[i][j] - b[i - t][j] - b[i][j - t] + b[i - t][j - t] == t * t) { dp[i - t + 1][j - t + 1]++; dp[i - t + 1][j + 1]--; dp[i + 1][j - t + 1]--; dp[i + 1][j + 1]++; } } } f = 0; for (i = 1; i <= n; i++) { for (j = 1; j <= m; j++) { dp[i][j] = dp[i][j] + dp[i - 1][j] + dp[i][j - 1] - dp[i - 1][j - 1]; if (dp[i][j] && !a[i][j]) f = 1; if (!dp[i][j] && a[i][j]) f = 1; } } if (!f) l = t2; else r = t2; } cout << l << endl; t = l * 2 + 1; for (i = 0; i <= n + 1; i++) { for (j = 0; j <= m + 1; j++) { dp[i][j] = 0; } } for (i = t; i <= n; i++) { for (j = t; j <= m; j++) { if (b[i][j] - b[i - t][j] - b[i][j - t] + b[i - t][j - t] == t * t) { dp[i - l][j - l] = 1; } } } for (i = 1; i <= n; i++) { for (j = 1; j <= m; j++) { if (dp[i][j]) printf("X"); else printf("."); } printf("\n"); } }
#include <bits/stdc++.h> using namespace std; template <typename T> inline const T read1() { T m = 0; char k = getchar(); while (('0' > k || k > '9') && (k != '-')) k = getchar(); const bool f = (k == '-' ? 1 : 0); if (f) k = getchar(); while ('0' <= k && k <= '9') m = (m << 3) + (m << 1) + (k ^ 48), k = getchar(); return f ? -m : m; } int s, m, **a, t; char **str; bool **vis, **h; queue<pair<int, int> > q; bool judge(int n) { while (!q.empty()) q.pop(); int len = n << 1 | 1, op = 0; for (int i = 1; i <= s; ++i) for (int j = 1; j <= m; ++j) vis[i][j] = h[i][j]; for (int i = 1; i <= s - len + 1; ++i) for (int j = 1; j <= m - len + 1; ++j) if (!(a[i + len - 1][j + len - 1] - a[i - 1][j + len - 1] - a[i + len - 1][j - 1] + a[i - 1][j - 1])) q.push(make_pair(i + n, j + n)), ++op, vis[i + n][j + n] = 1; for (int i = 1; i <= n; ++i) { int k = q.size(); while (k--) { int x = q.front().first, y = q.front().second; q.pop(); for (int tx = -1; tx <= 1; ++tx) for (int ty = -1; ty <= 1; ++ty) if (x + tx && x + tx <= s && y + ty && y + ty <= m && !vis[x + tx][y + ty]) { vis[x + tx][y + ty] = 1; q.push(make_pair(x + tx, y + ty)); ++op; } } } return op == t; } int main() { s = read1<int>(), m = read1<int>(); str = new char *[s + 5]; a = new int *[s + 5]; vis = new bool *[s + 5]; h = new bool *[s + 5]; a[0] = new int[m + 5](); vis[0] = new bool[m + 5](); h[0] = new bool[m + 5](); for (int i = 1; i <= s; ++i) { str[i] = new char[m + 5]; vis[i] = new bool[m + 5](); h[i] = new bool[m + 5](); a[i] = new int[m + 5](); scanf("%s", str[i] + 1); for (int j = 1; j <= m; ++j) a[i][j] = a[i - 1][j] + a[i][j - 1] - a[i - 1][j - 1] + (h[i][j] = str[i][j] == '.'), t += str[i][j] == 'X'; } int l = 1, r = min(s, m) - 1 >> 1, ans = 0, mid; while (l <= r) judge(mid = l + r >> 1) ? ans = mid, l = mid + 1 : r = mid - 1; printf("%d\n", ans); for (int i = 1; i <= s; ++i) for (int j = 1; j <= m; ++j) vis[i][j] = 0; int len = ans << 1 | 1; for (int i = 1; i <= s - len + 1; ++i) for (int j = 1; j <= m - len + 1; ++j) if (!(a[i + len - 1][j + len - 1] - a[i - 1][j + len - 1] - a[i + len - 1][j - 1] + a[i - 1][j - 1])) vis[i + ans][j + ans] = 1; for (int i = 1; i <= s; ++i, putchar('\n')) for (int j = 1; j <= m; ++j) putchar(vis[i][j] ? 'X' : '.'); return 0; }
#include <bits/stdc++.h> using namespace std; int n, m; vector<pair<int, int>> ans; bool check(int d, vector<vector<int>> a, string *s) { int ps[n + 2][m + 2]; ans.clear(); memset(ps, 0, sizeof ps); for (int i = 1; i + d <= n + 1; i++) for (int j = 1; j + d <= m + 1; j++) if (a[i][j] - a[i + d][j] - a[i][j + d] + a[i + d][j + d] == d * d) { ans.push_back({i + d / 2, j + d / 2}); ps[i][j]++; ps[i][j + d]--; ps[i + d][j]--; ps[i + d][j + d]++; } for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) ps[i][j] += ps[i][j - 1] + ps[i - 1][j] - ps[i - 1][j - 1]; for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) if (ps[i + 1][j + 1] == 0 && s[i][j] == 'X') return false; return true; } int main() { ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0); cin >> n >> m; string s[n]; for (int i = 0; i < n; i++) cin >> s[i]; vector<vector<int>> a(n + 2, vector<int>(m + 2, 0)); for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) a[i + 1][j + 1] = s[i][j] == 'X'; for (int i = n; i > 0; i--) for (int j = m; j > 0; j--) a[i][j] += a[i][j + 1] + a[i + 1][j] - a[i + 1][j + 1]; int l = 0, r = 500; while (r - l > 1) { int mid = l + r >> 1; check(mid * 2 + 1, a, s) ? l = mid : r = mid; } cout << l << endl; check(l * 2 + 1, a, s); bool c[n][m]; memset(c, 0, sizeof c); for (auto [x, y] : ans) c[x - 1][y - 1] = 1; for (int i = 0; i < n; i++, cout << '\n') for (int j = 0; j < m; j++) cout << (c[i][j] ? 'X' : '.'); }
#include <bits/stdc++.h> using namespace std; const long long N = 1e6 + 10; long long n, m, ans, cnt, tot; vector<vector<char> > ch(N), out(N); vector<vector<long long> > sum(N); bool check(long long mid) { long long cnt[n + 2][m + 2]; memset(cnt, 0, sizeof(cnt)); for (long long i = 2 * mid + 1; i <= n; i++) { for (long long j = 2 * mid + 1; j <= m; j++) { if (ch[i][j] == 'X' && (sum[i][j] + sum[i - 2 * mid - 1][j - 2 * mid - 1] - sum[i][j - 2 * mid - 1] - sum[i - 2 * mid - 1][j]) == (2 * mid + 1) * (2 * mid + 1)) cnt[i + 1][j + 1]++, cnt[i - 2 * mid][j - 2 * mid]++, cnt[i + 1][j - 2 * mid]--, cnt[i - 2 * mid][j + 1]--; } } for (long long i = 1; i <= n; i++) { for (long long j = 1; j <= m; j++) { cnt[i][j] = cnt[i - 1][j] + cnt[i][j - 1] - cnt[i - 1][j - 1] + cnt[i][j]; if ((cnt[i][j] > 0 && ch[i][j] == '.') || (cnt[i][j] <= 0 && ch[i][j] == 'X')) return 0; } } return 1; } void solve() { cin >> n >> m; for (long long i = 0; i <= n + 1; i++) { ch[i].resize(m + 2); out[i].resize(m + 2); sum[i].resize(m + 2); for (long long j = 1; j <= m && i <= n && i; j++) out[i][j] = '.', cin >> ch[i][j]; } for (long long j = 1; j <= m; j++) { cnt = 0; for (long long i = 1; i <= n; i++) { if (ch[i][j] == 'X') cnt++; sum[i][j] = sum[i][j - 1] + cnt; } } long long s = 1, e = min(n / 2, m / 2); while (s <= e) { long long mid = (s + e) / 2; if (check(mid)) { s = mid + 1; ans = mid; } else e = mid - 1; } cout << ans << '\n'; cnt = (2 * ans + 1) * (2 * ans + 1); for (long long i = 2 * ans + 1; i <= n; i++) { for (long long j = 2 * ans + 1; j <= m; j++) { if (ch[i][j] == 'X' && (sum[i][j] + sum[i - 2 * ans - 1][j - 2 * ans - 1] - sum[i][j - 2 * ans - 1] - sum[i - 2 * ans - 1][j]) == cnt) out[i - ans][j - ans] = 'X'; } } for (long long i = 1; i <= n; i++) { for (long long j = 1; j <= m; j++) { cout << out[i][j]; } cout << '\n'; } } signed main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); long long t = 1; clock_t start, end; start = clock(); cout << fixed << setprecision(8); while (t--) { solve(); } end = clock(); double time_taken = double(end - start) / double(CLOCKS_PER_SEC); }
#include <bits/stdc++.h> using namespace std; vector<vector<char> > a; vector<vector<int> > pref, val, dp; int n, m; inline int get_sum(int lx, int ly, int rx, int ry) { if (lx <= 0 || ly <= 0 || rx > n || ry > m) return 0; return (pref[rx][ry] - pref[rx][ly - 1] - pref[lx - 1][ry] + pref[lx - 1][ly - 1]) == (rx - lx + 1) * (ry - ly + 1); } inline void add(int lx, int ly, int rx, int ry) { val[lx][ly]++; val[lx][ry + 1]--; val[rx + 1][ly]--; val[rx + 1][ry + 1]++; } inline int oks(int x) { for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) val[i][j] = 0; } for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) { if (get_sum(i - x, j - x, i + x, j + x)) { add(i - x, j - x, i + x, j + x); } } } for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) { dp[i][j] = dp[i - 1][j] + dp[i][j - 1] - dp[i - 1][j - 1] + val[i][j]; assert(dp[i][j] >= 0); if (a[i][j] == 'X' && dp[i][j] == 0) return 0; } } return 1; } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n >> m; for (int i = 0; i <= n + 1; ++i) { a.emplace_back(); pref.emplace_back(); val.emplace_back(); dp.emplace_back(); for (int j = 0; j <= m + 1; ++j) { a.back().push_back('a'); pref.back().push_back(0); val.back().push_back(0); dp.back().push_back(0); } } for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) cin >> a[i][j]; } for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) { pref[i][j] = pref[i - 1][j] + pref[i][j - 1] - pref[i - 1][j - 1]; if (a[i][j] == 'X') pref[i][j]++; } } int lef = -1, righ = max(n, m) + 1; while (righ - lef > 1) { int mid = (righ + lef) / 2; if (oks(mid)) lef = mid; else righ = mid; } cout << lef << '\n'; for (int i = 1; i <= n; ++i) { for (int j = 1; j <= m; ++j) { if (get_sum(i - lef, j - lef, i + lef, j + lef)) cout << 'X'; else cout << '.'; } cout << '\n'; } return 0; }
#include <bits/stdc++.h> using namespace std; int n, m; int total_num = 0; int* pool; int** grid; int* prefix_sum_pool; int** prefix_sum; int* prefix2_pool; int** prefix2; int get_sum(int minR, int minC, int maxR, int maxC) { return prefix_sum[maxR][maxC] - (minR == 0 ? 0 : prefix_sum[minR - 1][maxC]) - (minC == 0 ? 0 : prefix_sum[maxR][minC - 1]) + (minR == 0 || minC == 0 ? 0 : prefix_sum[minR - 1][minC - 1]); } bool works(int time) { int len = 2 * time + 1; for (int i = 0; i < n * m; i++) { prefix2_pool[i] = 0; } prefix_sum[0][0] = grid[0][0]; for (int i = 1; i < m; i++) { prefix_sum[0][i] = prefix_sum[0][i - 1] + grid[0][i]; } for (int i = 1; i < n; i++) { prefix_sum[i][0] = prefix_sum[i - 1][0] + grid[i][0]; } for (int i = 1; i < n; i++) { for (int j = 1; j < m; j++) { prefix_sum[i][j] = prefix_sum[i - 1][j] + prefix_sum[i][j - 1] - prefix_sum[i - 1][j - 1] + grid[i][j]; } } vector<pair<int, int>> centers; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { int minR = i - time; int minC = j - time; int maxR = i + time; int maxC = j + time; if (minR < 0 || minC < 0 || maxR >= n || maxC >= m) continue; int sum = get_sum(minR, minC, maxR, maxC); if (sum == len * len) { centers.push_back({i, j}); for (int i = minR; i <= maxR; i++) { prefix2[i][minC] += 1; if (maxC + 1 < m) prefix2[i][maxC + 1] -= 1; } } } } int count = 0; for (int i = 0; i < n; i++) { int running_sum = 0; for (int j = 0; j < m; j++) { running_sum += prefix2[i][j]; if (running_sum > 0) count++; } } return count == total_num; } void gen_config(int time) { bool* thing = new bool[n * m]; bool** thing2 = new bool*[n]; for (int i = 0; i < n; i++) { thing2[i] = thing + i * m; } for (int i = 0; i < n * m; i++) { thing[i] = false; } int len = 2 * time + 1; for (int i = 0; i < n * m; i++) { prefix2_pool[i] = 0; } prefix_sum[0][0] = grid[0][0]; for (int i = 1; i < m; i++) { prefix_sum[0][i] = prefix_sum[0][i - 1] + grid[0][i]; } for (int i = 1; i < n; i++) { prefix_sum[i][0] = prefix_sum[i - 1][0] + grid[i][0]; } for (int i = 1; i < n; i++) { for (int j = 1; j < m; j++) { prefix_sum[i][j] = prefix_sum[i - 1][j] + prefix_sum[i][j - 1] - prefix_sum[i - 1][j - 1] + grid[i][j]; } } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { int minR = i - time; int minC = j - time; int maxR = i + time; int maxC = j + time; if (minR < 0 || minC < 0 || maxR >= n || maxC >= m) continue; int sum = get_sum(minR, minC, maxR, maxC); if (sum == len * len) { thing2[i][j] = true; } } } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { cout << (thing2[i][j] ? 'X' : '.'); } cout << '\n'; } delete[] thing; delete[] thing2; } int main() { cin >> n >> m; pool = new int[n * m]; prefix_sum_pool = new int[n * m]; prefix2_pool = new int[n * m]; for (int i = 0; i < n * m; i++) { pool[i] = 0; prefix_sum_pool[i] = 0; prefix2_pool[i] = 0; } grid = new int*[n]; prefix_sum = new int*[n]; prefix2 = new int*[n]; for (int i = 0; i < n; i++) { grid[i] = pool + i * m; prefix_sum[i] = prefix_sum_pool + i * m; prefix2[i] = prefix2_pool + i * m; } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { char c = 0; cin >> c; grid[i][j] = c == 'X'; } } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { total_num += grid[i][j]; } } int low = 0; int high = min(n / 2, m / 2) + 1; int last_worked = 0; while (low < high) { int mid = (low + high) / 2; if (works(mid)) { last_worked = mid; low = mid + 1; } else { high = mid; } } cout << last_worked << endl; gen_config(last_worked); delete[] pool; delete[] grid; delete[] prefix_sum; delete[] prefix_sum_pool; delete[] prefix2_pool; delete[] prefix2; }
#include <bits/stdc++.h> using namespace std; const int DX[] = {-1, -1, 0, +1, +1, +1, 0, -1}; const int DY[] = {0, +1, +1, +1, 0, -1, -1, -1}; const int INF = 1e9; int n, m; vector<vector<bool> > f; vector<pair<int, int> > fired; vector<vector<int> > pref; vector<pair<int, int> > ans; int get_sum(int x1, int y1, int x2, int y2) { return pref[x2][y2] + pref[x1 - 1][y1 - 1] - pref[x1 - 1][y2] - pref[x2][y1 - 1]; } bool check(int i, int j, int mid) { int x1 = i - mid; int y1 = j - mid; int x2 = i + mid; int y2 = j + mid; return x1 >= 0 && x1 < n && y1 >= 0 && y1 < m && x2 >= 0 && x2 < n && y2 >= 0 && y2 < m && (get_sum(x1 + 1, y1 + 1, x2 + 1, y2 + 1) == (x2 - x1 + 1) * (y2 - y1 + 1)); } bool ch(int mid) { queue<pair<int, int> > q; vector<pair<int, int> > lists; vector<vector<int> > d(n, vector<int>(m, INF)); for (int i = (0); i < (n); i++) { for (int j = (0); j < (m); j++) { if (check(i, j, mid)) { q.push({i, j}); lists.push_back({i, j}); d[i][j] = 0; } } } while (!q.empty()) { int x, y; tie(x, y) = q.front(); q.pop(); for (int i = 0; i < 8; i++) { int v = x + DX[i]; int u = y + DY[i]; if (v >= 0 && v < n && u >= 0 && u < m) { if (d[x][y] + 1 < d[v][u]) { d[v][u] = d[x][y] + 1; q.push({v, u}); } } } } for (auto elem : fired) { if (d[elem.first][elem.second] > mid) { return false; } } ans = lists; return true; } void precalc() { for (int i = (0); i < (n); i++) { for (int j = (0); j < (m); j++) { pref[i + 1][j + 1] = pref[i + 1][j] + pref[i][j + 1] - pref[i][j] + f[i][j]; } } } void solve() { precalc(); int l = -1; int r = min(n, m) + 1; while (r - l > 1) { int mid = (l + r) / 2; if (ch(mid)) { l = mid; } else { r = mid; } } cout << l << "\n"; vector<vector<int> > answer(n, vector<int>(m, 0)); for (auto elem : ans) { answer[elem.first][elem.second] = 1; } for (auto& elem : answer) { for (auto& elem2 : elem) { if (elem2) { cout << 'X'; } else { cout << '.'; } } cout << "\n"; } } int main() { ios_base::sync_with_stdio(0); cin.tie(0); ; cin >> n >> m; f.resize(n, vector<bool>(m, false)); pref.resize(n + 1, vector<int>(m + 1, 0)); for (int i = (0); i < (n); i++) { for (int j = (0); j < (m); j++) { char tmp; cin >> tmp; if (tmp == 'X') { f[i][j] = 1; fired.push_back({i, j}); } } } solve(); return 0; }
#include <bits/stdc++.h> using namespace std; using ll = long long; const ll N = 1e6 + 100; ll n; ll m; ll **arr() { ll **res = new ll *[n + 2]; for (ll i = 0; i < n + 2; ++i) { res[i] = new ll[m + 2]; fill_n(res[i], m + 2, 0); } return res; } ll **inp; ll **ans; void pref(ll **a) { for (ll i = 1; i <= n + 1; ++i) { for (ll j = 1; j <= m + 1; ++j) { a[i][j] += a[i - 1][j] + a[i][j - 1] - a[i - 1][j - 1]; } } } ll sum(ll **a, ll il, ll ir, ll jl, ll jr) { il = max(il, 1ll); ir = min(ir, n); jl = max(jl, 1ll); jr = min(jr, m); --il; --jl; return a[ir][jr] - a[ir][jl] - a[il][jr] + a[il][jl]; } ll sq(ll first) { return first * first; } bool check(ll t) { for (ll i = 1; i <= n; ++i) { for (ll j = 1; j <= m; ++j) { ans[i][j] = sum(inp, i - t, i + t, j - t, j + t) == sq(2 * t + 1); } } pref(ans); for (ll i = 1; i <= n; ++i) { for (ll j = 1; j <= m; ++j) { if (sum(inp, i, i, j, j) && sum(ans, i - t, i + t, j - t, j + t) == 0) { return false; } } } return true; } signed main() { ios::sync_with_stdio(0); cin.tie(0); cin >> n >> m; inp = arr(); ans = arr(); for (ll i = 1; i <= n; ++i) { string s; cin >> s; for (ll j = 1; j <= m; ++j) { inp[i][j] = s[j - 1] == 'X'; } } pref(inp); ll lef = 0, rig = N; while (rig - lef > 1) { ll mid = (lef + rig) / 2; if (check(mid)) { lef = mid; } else { rig = mid; } } assert(check(lef)); cout << lef << "\n"; for (ll i = 1; i <= n; ++i) { for (ll j = 1; j <= m; ++j) { cout << ".X"[sum(ans, i, i, j, j)]; } cout << "\n"; } return 0; }
#include <bits/stdc++.h> using namespace std; int dir[8][2] = {{-1, -1}, {-1, 0}, {-1, 1}, {1, 0}, {1, -1}, {1, 1}, {0, 1}, {0, -1}}; int n, m; vector<vector<int> > grid, dist, visited; string s[1000010]; bool check(int x, int y) { if (x >= 1 && y >= 1 && x <= n && y <= m && s[x][y] == 'X') return true; return false; } int getsumi(int i, int j, int a, int b) { return grid[a][b] - grid[i - 1][b] - grid[a][j - 1] + grid[i - 1][j - 1]; } int main() { ios::sync_with_stdio(false); cin.tie(NULL); cin >> n >> m; int tot = 0; for (int i = 1; i <= n; i++) { cin >> s[i]; s[i] = "?" + s[i]; } vector<int> temp(m + 1); for (int i = 0; i <= n; i++) { grid.push_back(temp); visited.push_back(temp); dist.push_back(temp); } for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { grid[i][j] += grid[i][j - 1] + grid[i - 1][j] - grid[i - 1][j - 1]; if (s[i][j] == 'X') { tot++; grid[i][j] += 1; } } } int low = 1, high = min(n, m); while (low < high) { int mid = (low + high) / 2; for (int i = 1; i <= n; i++) for (int j = 1; j <= m; j++) visited[i][j] = 0, dist[i][j] = 0; vector<pair<int, int> > sources; for (int i = 1; i + 2 * mid <= n; i++) { for (int j = 1; j + 2 * mid <= m; j++) { if (getsumi(i, j, i + 2 * mid, j + 2 * mid) == 1LL * (2 * mid + 1) * (2 * mid + 1)) { sources.push_back(make_pair(i + mid, j + mid)); } } } queue<pair<int, int> > pq; for (auto val : sources) { pq.push(val); visited[val.first][val.second] = 1; } int ans = 0; while (pq.size()) { pair<int, int> ft = pq.front(); ans++; pq.pop(); int x = ft.first; int y = ft.second; if (dist[x][y] == mid) continue; for (int i = 0; i < 8; i++) { int p = x + dir[i][0]; int q = y + dir[i][1]; if (check(p, q)) { if (!visited[p][q]) { dist[p][q] = dist[x][y] + 1; visited[p][q] = 1; pq.push({p, q}); } } } } if (ans < tot) high = mid; else low = mid + 1; } int ans = low - 1; cout << ans << '\n'; vector<pair<int, int> > sources; for (int i = 1; i + 2 * ans <= n; i++) { for (int j = 1; j + 2 * ans <= m; j++) { if (getsumi(i, j, i + 2 * ans, j + 2 * ans) == 1LL * (2 * ans + 1) * (2 * ans + 1)) { sources.push_back(make_pair(i + ans, j + ans)); } } } for (int i = 1; i <= n; i++) { for (int j = 1; j <= m; j++) { s[i][j] = '.'; } } for (int i = 0; i < sources.size(); i++) { s[sources[i].first][sources[i].second] = 'X'; } for (int i = 1; i <= n; i++) { cout << s[i].substr(1, m) << '\n'; } }
#include <bits/stdc++.h> using namespace std; int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr); int n, m; cin >> n >> m; int a[n][m]; for (int i = 0; i < n; ++i) { string s; cin >> s; for (int j = 0; j < m; ++j) { if (s[j] == 'X') { a[i][j] = 1; } else { a[i][j] = 0; } } } int x[] = {1, -1, -1, 1, 0, 1, 0, -1}; int y[] = {-1, 1, -1, 1, 1, 0, -1, 0}; int pref[n + 1][m + 1]; for (int k = 0; k < n + 1; ++k) { pref[k][0] = 0; } for (int l = 0; l < m + 1; ++l) { pref[0][l] = 0; } for (int i = 1; i < n + 1; ++i) { for (int j = 1; j < m + 1; ++j) { pref[i][j] = a[i - 1][j - 1] + pref[i][j - 1] + pref[i - 1][j] - pref[i - 1][j - 1]; } } int l = 0; int r = min(n, m) + 1; while (l + 1 != r) { int mid = (l + r) / 2; int d = mid * 2 + 1; int t[n][m]; int dist[n][m]; bool used[n][m]; for (int k = 0; k < n; ++k) { for (int i = 0; i < m; ++i) { t[k][i] = 0; dist[k][i] = 1e9; used[k][i] = false; } } for (int i = 0; i <= n - d; ++i) { for (int j = 0; j <= m - d; ++j) { int sum = pref[i + d][j + d] - pref[i + d][j] - pref[i][j + d] + pref[i][j]; if (sum == d * d) { t[i + mid][j + mid] = 1; } } } queue<pair<int, int>> q; for (int i = 0; i < n; ++i) { for (int j = 0; j < m; ++j) { if (t[i][j] == 1) { q.push({i, j}); used[i][j] = true; dist[i][j] = 0; } } } while (q.size() != 0) { int xx = (q.front()).first; int yy = q.front().second; q.pop(); for (int i = 0; i < 8; ++i) { int xxx = xx + x[i]; int yyy = yy + y[i]; if (xxx >= 0 && xxx < n && yyy >= 0 && yyy < m && !used[xxx][yyy]) { dist[xxx][yyy] = dist[xx][yy] + 1; used[xxx][yyy] = true; q.push({xxx, yyy}); } } } bool good = true; for (int i = 0; i < n; ++i) { for (int j = 0; j < m; ++j) { if (a[i][j] == 1) { if (dist[i][j] > mid) { good = false; } } } } if (good) l = mid; else r = mid; } cout << l << "\n"; int mid = l; int d = mid * 2 + 1; int t[n][m]; int used[n][m]; int add[n][m]; for (int k = 0; k < n; ++k) { for (int i = 0; i < m; ++i) { t[k][i] = 0; used[k][i] = 0; } } for (int i = 0; i <= n - d; ++i) { for (int j = 0; j <= m - d; ++j) { int sum = pref[i + d][j + d] - pref[i + d][j] - pref[i][j + d] + pref[i][j]; if (sum == d * d) { used[i][j] += 1; used[i + d - 1][j + d - 1] -= 1; add[i + d - 1][j + d - 1] += 1; t[i + mid][j + mid] = 1; } } } for (int i = 0; i < n; ++i) { for (int j = 0; j < m; ++j) { if (t[i][j] == 1) { cout << "X"; } else { cout << "."; } } cout << "\n"; } }
#include <bits/stdc++.h> using namespace std; int n, m; vector<long long int> v[1000010]; vector<long long int> cum[1000010]; vector<long long int> amid[1000010]; void build() { cum[0][0] = v[0][0]; for (int i = 1; i < m; i++) cum[0][i] = cum[0][i - 1] + v[0][i]; for (int i = 1; i < n; i++) cum[i][0] = cum[i - 1][0] + v[i][0]; for (int i = 1; i < n; i++) { for (int j = 1; j < m; j++) { cum[i][j] = cum[i - 1][j] + cum[i][j - 1] - cum[i - 1][j - 1] + v[i][j]; } } return; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { cout << cum[i][j] << " "; } cout << '\n'; } } long long int get(int sx, int sy, long long int c) { int ex = sx + 2 * c, ey = sy + 2 * c; long long int ret = cum[ex][ey]; if (sx) ret -= cum[sx - 1][ey]; if (sy) ret -= cum[ex][sy - 1]; if (sx && sy) ret += cum[sx - 1][sy - 1]; return ret; } int dx[] = {1, 1, 1, 0, 0, -1, -1, -1}; int dy[] = {0, 1, -1, 1, -1, 0, 1, -1}; bool in(int x, int y) { return x >= 0 && x < n && y >= 0 && y < m; } bool ok(int c) { for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { amid[i][j] = -1; } } queue<pair<long long int, long long int> > q; long long int s = (2 * c + 1) * (2 * c + 1); for (int i = 0; i + 2 * c + 1 <= n; i++) { for (int j = 0; j + 2 * c + 1 <= m; j++) { long long int x = get(i, j, c); if (x == s) { amid[i + c][j + c] = 0; q.push({i + c, j + c}); } } } while (!q.empty()) { pair<long long int, long long int> cur = q.front(); q.pop(); if (amid[cur.first][cur.second] == c) continue; for (int i = 0; i < 8; i++) { int nx = cur.first + dx[i]; int ny = cur.second + dy[i]; if (in(nx, ny) && amid[nx][ny] == -1) { amid[nx][ny] = amid[cur.first][cur.second] + 1; q.push({nx, ny}); } } } for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (v[i][j] == 1 && amid[i][j] == -1) return 0; if (v[i][j] == 0 && amid[i][j] != -1) return 0; } } return 1; } int main() { cin >> n >> m; int mn = 1000000; for (int i = 0; i < n; i++) { int cnt = 0; for (int j = 0; j < m; j++) { char c; amid[i].push_back(0); cum[i].push_back(0); scanf(" %c", &c); int x = 0; if (c == 'X') x = 1; v[i].push_back(x); if (x == 1) cnt++; else { if (cnt) mn = min(mn, cnt); cnt = 0; } } if (cnt) mn = min(mn, cnt); } for (int j = 0; j < m; j++) { int cnt = 0; for (int i = 0; i < n; i++) { if (v[i][j] == 1) cnt++; else { if (cnt) mn = min(mn, cnt); cnt = 0; } } if (cnt) mn = min(mn, cnt); } build(); int st = 0, en = 1000000; while (st + 1 < en) { int md = (st + en) / 2; if (ok(md)) st = md; else en = md; } cout << st << '\n'; ok(st); for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { if (amid[i][j] == 0) cout << "X"; else cout << "."; } cout << '\n'; } }
#include <bits/stdc++.h> using namespace std; string s; void comp_z(vector<long> &z) { long n = z.size(); z[0] = n; long L = -1, R = -1; for (int i = 1; i < n; i++) { if (R < i) { L = R = i; while (R < n && s[R] == s[R - L]) R++; z[i] = R - L; R--; } else { long k = i - L; if (z[k] < (R - i + 1)) { z[i] = z[k]; } else { L = i; while (R < n && s[R] == s[R - L]) R++; z[i] = R - L; R--; } } } } int main(void) { cin >> s; int n = s.length(); vector<long> z(n, 0); comp_z(z); long mx = 0, res = 0; long i; for (i = 1; i < n; i++) { if (z[i] == (n - i) && mx >= (n - i)) { res = n - i; break; } mx = max(mx, z[i]); } if (res) cout << s.substr(0, res); else cout << "Just a legend"; }
#include <bits/stdc++.h> using namespace std; int main() { int hash[26] = {0}; string s; cin >> s; int n = s.length(); if (n == 1) { cout << "Just a legend\n"; return 0; } if (n >= 3) { for (int i = 0; i < n; i++) { hash[(int)s[i] - 'a']++; } int ct = 0; for (int i = 0; i < 26; i++) { if (hash[i] > 0) ct++; } if (ct == 1) { for (int i = 0; i < n - 2; i++) cout << s[i]; cout << "\n"; return 0; } } int z[1000006]; int L = 0, R = 0; for (int i = 1; i < n; i++) { if (i > R) { L = R = i; while (R < n && s[R - L] == s[R]) R++; z[i] = R - L; R--; } else { int k = i - L; if (z[k] < R - i + 1) z[i] = z[k]; else { L = i; while (R < n && s[R - L] == s[R]) R++; z[i] = R - L; R--; } } } set<pair<int, int> > st; int steps = 0; for (int i = n - 1; i >= 0; i--) { steps++; if (steps == z[i]) { st.insert(pair<int, int>(z[i], i)); } } set<pair<int, int> >::reverse_iterator it; int start = -1, len = 0; for (it = st.rbegin(); it != st.rend(); it++) { if (len < it->first) for (int i = 0; i < it->second; i++) { if (z[i] >= it->first) { start = i; len = it->first; } } } if (start == -1) { cout << "Just a legend\n"; return 0; } for (int i = start; i < start + len; i++) cout << s[i]; cout << "\n"; return 0; }
#include <bits/stdc++.h> using namespace std; const int maxN = 1e6 + 10; string s; int z[maxN]; int main() { ios_base::sync_with_stdio(0), cin.tie(0); cin >> s; int l, r; l = r = 0; for (int i = 1; i < s.size(); ++i) { if (i > r) { l = r = i; while (r < s.size() && s[r - l] == s[r]) ++r; z[i] = r - l; --r; } else { int k = i - l; z[i] = min(z[k], r - i + 1); if (z[i] >= r - i + 1) { l = i; while (r < s.size() && s[r - l] == s[r]) ++r; z[i] = r - l; --r; } } } int ans, mx; ans = -1, mx = 0; for (int i = 1; i < s.size(); ++i) { if (i + z[i] == s.size() && z[i] <= mx) { ans = z[i]; break; } mx = max(mx, z[i]); } if (ans != -1) for (int i = 0; i < ans; ++i) cout << s[i]; else cout << "Just a legend"; return 0; }
#include <bits/stdc++.h> using namespace std; int lim = 1000000; int mod = 1000000000 + 7; int inf = 1000000000; int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); string s; cin >> s; const string t = "Just a legend"; int n = (int)s.length(); vector<int> pi(n); pi[0] = 0; for (int i = 1; i < n; i++) { int j = pi[i - 1]; while (j > 0 && s[i] != s[j]) { j = pi[j - 1]; } if (s[i] == s[j]) { j++; } pi[i] = j; } if (pi[n - 1] == 0) { cout << t; } else { int p = 0; for (int i = 1; i < n - 1; i++) { if (pi[i] == pi[n - 1]) { p = 1; break; } } if (p) { for (int i = 0; i < pi[n - 1]; i++) { cout << s[i]; } } else { if (pi[pi[n - 1] - 1] == 0) { cout << t; } else { int p1 = 0; for (int i = 1; i < n - 1; i++) { if (pi[i] == pi[pi[n - 1] - 1]) { p1 = 1; break; } } if (p1) { for (int i = 0; i < pi[pi[n - 1] - 1]; i++) { cout << s[i]; } } else { cout << t; } } } } }
#include <bits/stdc++.h> using namespace std; int main() { string s; cin >> s; int n = s.size(); vector<int> prefix(n); for (int i = 1, k = 0; i < n; i++) { while (k > 0 && s[k] != s[i]) k = prefix[k - 1]; if (s[i] == s[k]) prefix[i] = ++k; else prefix[i] = k; } int j = n, l; while (1) { l = j - 1; j = prefix[l]; if (j == 0) break; for (int i = 0; i < (int)(n - 1); i++) if (prefix[i] >= j) { cout << s.substr(n - j) << endl; return 0; } } cout << "Just a legend\n"; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000023; long long int power(long long int a, long long int b) { long long int ans = 1; while (b) { if (b & 1) ans = (ans * a); b /= 2; a = (a * a); } return ans; } bool sortbysec(const pair<long long int, long long int> &a, const pair<long long int, long long int> &b) { if (a.first > b.first) return 1; else if (a.first == b.first) return (a.second < b.second); else return 0; } long long int hash1[N]; long long int p_pow[N]; string str; long long int n; void cal_pow() { long long int p = 31; for (long long int i = 0; i < N; i++) { if (i != 0) p_pow[i] = (p_pow[i - 1] * p) % 1000000007; else p_pow[i] = 1; } } void calc() { hash1[0] = str[0] - 'a' + 1; for (long long int i = 1; i <= str.size() - 1; i++) { hash1[i] = (hash1[i - 1] + (p_pow[i] * (str[i] - 'a' + 1)) % 1000000007) % 1000000007; } } long long int check(long long int val, long long int len) { for (long long int i = 1; i < n - len; i++) { long long int temp = (p_pow[n - 1 - i] * (hash1[i + len - 1] - hash1[i - 1] + 1000000007) % 1000000007) % 1000000007; if (temp == val) return 1; } return 0; } void solve() { cin >> str; cal_pow(); calc(); vector<pair<long long int, long long int>> v; n = str.size(); for (long long int i = 0; i < n - 1; i++) { long long int f = (p_pow[n - 1] * hash1[i]) % 1000000007; long long int s = (p_pow[i] * (hash1[n - 1] - hash1[n - i - 2] + 1000000007) % 1000000007) % 1000000007; if (f == s) v.push_back({i + 1, f}); } if (!v.size()) { cout << "Just a legend" << endl; return; } sort((v).begin(), (v).end()); v.push_back({n + 3, 1}); long long int l = 0, r = v.size() - 1; if (!check(v[0].second, v[0].first)) { cout << "Just a legend" << endl; return; } while ((l + 1) < r) { long long int mid = (l + r) / 2; if (check(v[mid].second, v[mid].first)) l = mid; else r = mid; } long long int idx = 0, len = v[l].first; while (len--) { cout << str[idx]; idx++; } } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); long long int Test; Test = 1; long long int t = 0; while (t++ < Test) { solve(); } cerr << "Time : " << 1000 * ((double)clock()) / (double)CLOCKS_PER_SEC << "ms\n"; }
#include <bits/stdc++.h> using namespace std; int main() { cin.tie(NULL); cout.tie(NULL); ios_base::sync_with_stdio(false); string s; cin >> s; int n = s.length(); int i, j, l = 0, r = 0; vector<int> z(n, 0); for (i = 1; i < n; i++) { if (i <= r) z[i] = min(r - i + 1, z[i - l]); while (z[i] + i < n && s[z[i]] == s[z[i] + i]) z[i]++; if (i + z[i] - 1 > r) { l = i; r = i + z[i] - 1; } } int mx[n], ans = -1; mx[0] = z[0]; for (i = 1; i < n; i++) mx[i] = max(mx[i - 1], z[i]); for (i = n - 1; i > 0; i--) { if (i + z[i] == n && mx[i - 1] >= z[i]) ans = i; } if (ans == -1) cout << "Just a legend\n"; else { for (int j = ans; j < n; j++) cout << s[j]; cout << "\n"; } return 0; }
#include <bits/stdc++.h> using namespace std; int maxstrlen = 1e6; unsigned long long mod[] = {(int)1e9 + 7, (int)1e9 + 9}; class RH { static vector<unsigned long long> x[2]; vector<unsigned long long> h[2]; string str; int n; unsigned long long hash(int a, int start, int len) { unsigned long long ans = 0, end = start + len; ans += h[a][start] - h[a][end] * x[a][len] % mod[a] + mod[a]; return ans % mod[a]; } public: RH() {} RH(const string &str) { this->str = str; n = str.size(); if (x[0].empty()) for (int a = 0; a < (int)2; ++a) { x[a].assign(maxstrlen + 1, 1); for (int i = 0; i < (int)maxstrlen; ++i) x[a][i + 1] = x[a][i] * 127 % mod[a]; } for (int a = 0; a < (int)2; ++a) { h[a].assign(n + 1, 0); for (int i = n - 1; i >= 0; --i) h[a][i] = (h[a][i + 1] * 127 + str[i]) % mod[a]; } } unsigned long long hash(int start, int len) { return hash(0, start, len) << 32 | hash(1, start, len); } }; vector<unsigned long long> RH::x[2]; int main() { string Texto; cin >> Texto; int Indice = -1; RH RoHa(Texto); for (int i = 0; i < Texto.size() - 1; ++i) { if (RoHa.hash(0, i + 1) == RoHa.hash(Texto.size() - 1 - i, i + 1)) { for (int j = 1; j + i < Texto.size() - 1; ++j) { if (RoHa.hash(0, i + 1) == RoHa.hash(j, i + 1)) { Indice = i; break; } } } } if (Indice == -1) { cout << "Just a legend" << endl; } else { cout << Texto.substr(0, Indice + 1); } }
#include <bits/stdc++.h> using namespace std; int T[1000010]; void preprocess(const string &Needle) { T[0] = -1; int i = 0, j = -1; while (i < Needle.size()) { while (j >= 0 && Needle[i] != Needle[j]) j = T[j]; j++; i++; T[i] = j; } } int F[1000010]; void Find(const string &Hay, const string &Needle) { preprocess(Needle); int i = 0, j = 0; while (i < Hay.size()) { while (j >= 0 && Needle[j] != Hay[i]) j = T[j]; i++, j++; } while (j >= 0) { F[i - j] = j; j = T[j]; } } int ok(const string &Hay, const string &Needle) { preprocess(Needle); int i = 1, j = 0; int ma = 0; while (i < Hay.size()) { while (j >= 0 && Needle[j] != Hay[i]) j = T[j]; i++, j++; if (i == Hay.size()) break; ma = max(j, ma); } return ma; } int main() { string A = "fixprefixsuffix"; cin >> A; Find(A, A); int ma = ok(A, A); int ans = 0; for (int i = 0; i < A.size() && ans == 0; ++i) if (F[i] <= ma) ans = F[i]; if (ans == 0) cout << "Just a legend" << endl; else cout << A.substr(0, ans) << endl; }
#include <bits/stdc++.h> using namespace std; vector<int> prefix_function(string s) { int n = (int)s.length(); vector<int> pi(n); for (int i = 1; i < n; i++) { int j = pi[i - 1]; while (j > 0 && s[i] != s[j]) j = pi[j - 1]; if (s[i] == s[j]) j++; pi[i] = j; } return pi; } int main() { ios::sync_with_stdio(false); cin.tie(NULL); string s; cin >> s; int f = 0; vector<int> v; v = prefix_function(s); if (v[s.length() - 1] == 0) { cout << "Just a legend"; return 0; } for (int i = v[s.length() - 1]; i < s.length() - 1; i++) { if (v[i] == v[s.length() - 1]) { f = 1; break; } } if (f == 1) { for (int i = 0; i < v[s.length() - 1]; i++) cout << s[i]; return 0; } if (v[v[s.length() - 1] - 1] > 0) { for (int i = 0; i < v[v[s.length() - 1] - 1]; i++) cout << s[i]; return 0; } cout << "Just a legend"; return 0; }
#include <bits/stdc++.h> using namespace std; const double EPS = 1e-9; const int INFMEM = 63; const int INF = 1061109567; const long long LINF = 4557430888798830399LL; const double DINF = numeric_limits<double>::infinity(); const long long MOD = 1000000007; const int dx[8] = {1, 0, -1, 0, 1, 1, -1, -1}; const int dy[8] = {0, 1, 0, -1, 1, -1, 1, -1}; const double PI = 3.141592653589793; inline void open(string a) { freopen((a + ".in").c_str(), "r", stdin); freopen((a + ".out").c_str(), "w", stdout); } inline void fasterios() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); } struct rollingHash { int base, curN; bool suffixOn; string *myString; vector<long long> precBase; vector<long long> hash[2]; explicit rollingHash(string *x, int curBase = 31, bool enableSuffix = 0, bool precomputeBase = 1) { myString = x; curN = myString->length(); base = curBase; suffixOn = enableSuffix; hash[0].resize(curN); if (enableSuffix) hash[1].resize(myString->length()); precBase.resize(curN); makeHash(); } void makeHash() { if (curN == 0) return; precBase[0] = 1; for (int i = 1; i < curN; i++) precBase[i] = (precBase[i - 1] * base) % MOD; for (int i = 0; i < curN; i++) { int curlet = (*myString)[i] - 'a'; hash[0][i] = (curlet * precBase[curN - i - 1]) % MOD; if (i) hash[0][i] = (hash[0][i] + hash[0][i - 1]) % MOD; if (suffixOn) { hash[1][i] = (curlet * precBase[i]) % MOD; if (i) hash[1][i] = (hash[1][i] + hash[1][i - 1]) % MOD; } } return; } inline long long getHash(int a, int b) { bool isSuffix = a > b; if (a > b) swap(a, b); return (hash[isSuffix][b] - (a - 1 >= 0 ? hash[isSuffix][a - 1] : 0) + MOD) % MOD; } bool isSame(pair<int, int> a, pair<int, int> b) { if (abs(a.first - a.second) != abs(b.first - b.second)) return 0; long long valA = getHash(a.first, a.second); long long valB = getHash(b.first, b.second); if (a.first <= a.second) a = {curN - a.second - 1, curN - a.first - 1}; else swap(a.first, a.second); if (b.first <= b.second) b = {curN - b.second - 1, curN - b.first - 1}; else swap(b.first, b.second); if (a.first > b.first) { swap(a, b); swap(valA, valB); } valA = (valA * precBase[b.first - a.first]) % MOD; return valA == valB; } bool isSame(pair<int, int> a, string &s, long long sHash) { int sLen = s.length(); sLen--; if (abs(a.first - a.second) != sLen) return 0; long long valA = getHash(a.first, a.second); if (a.first <= a.second) a = {curN - a.second - 1, curN - a.first - 1}; else swap(a.first, a.second); sHash = (sHash * precBase[a.first]) % MOD; return valA == sHash; } bool isPalindrome(int a, int b) { if (a == b) return 1; return isSame({a, b}, {b, a}); } }; long long getSingleHash(string &s, long long base = 31) { long long ret = 0; for (int i = 0; i < s.length(); i++) { ret = (ret * base); ret = (ret + (s[i] - 'a')) % MOD; } return ret; } int main() { fasterios(); string s; cin >> s; rollingHash hash1(&s, 31, 0, 1); rollingHash hash2(&s, 37, 0, 1); rollingHash hash3(&s, 41, 0, 1); int n = s.length(); n--; for (int i = n - 2; i >= 0; i--) { pair<int, int> a = {0, i}; pair<int, int> b = {n - i, n}; if (hash1.isSame(a, b) && hash2.isSame(a, b) && hash3.isSame(a, b)) { for (int j = 1;; j++) { int kanan = j + i; if (kanan == n) break; if (hash1.isSame(a, {j, kanan}) && hash2.isSame(a, {j, kanan}) && hash3.isSame(a, {j, kanan})) { for (int k = 0; k <= i; k++) cout << s[k]; cout << '\n'; return 0; } } } } cout << "Just a legend" << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; int32_t main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); string s; cin >> s; long long n = s.length(); vector<long long> lps(n, 0); for (long long i = 1; i < n; i++) { long long j = lps[i - 1]; while (j > 0 && s[i] != s[j]) { j = lps[j - 1]; } if (s[i] == s[j]) { j++; } lps[i] = j; } if (lps[n - 1] == 0) { cout << "Just a legend"; return 0; } long long yes = 0; for (long long i = 0; i < n - 1; i++) { if (lps[i] == lps[n - 1]) { cout << s.substr(0, lps[i]); return 0; } } long long z = lps[lps[n - 1] - 1]; if (z > 0) { cout << s.substr(0, z); return 0; } cout << "Just a legend"; return 0; }
#include <bits/stdc++.h> using namespace std; string s; int P[1000001], pr[1000001]; int i, j, c; int main() { getline(cin, s); if (int((s).size()) <= 2) { cout << "Just a legend" << endl; return 0; } pr[0] = 0; P[0] = 0; for (i = 1; i <= int((s).size()) - 1; i++) { j = pr[i - 1]; while (j > 0 && s[i] != s[j]) j = pr[j - 1]; if (s[i] == s[j]) j++; pr[i] = j; P[i] = max(P[i - 1], pr[i]); } j = pr[int((s).size()) - 1]; while (j > 0) { if (P[int((s).size()) - 2] >= j) { for (c = 0; c <= j - 1; c++) cout << s[c]; cout << endl; return 0; } j = pr[j - 1]; } cout << "Just a legend" << endl; }
#include <bits/stdc++.h> using namespace std; int kmp[1000007]; int i = 0; void doit(string b) { kmp[0] = 0; int lth = b.length(); for (int j = 1; j < (lth); j++) { while (b[j] != b[i] && i > 0) { i = kmp[i - 1]; } if (b[j] == b[i]) { i++; } else { i = 0; if (b[j] == b[0]) { i++; } } kmp[j] = i; } } int main() { string a; cin >> a; doit(a); vector<int> check; int x, y; x = kmp[a.length() - 1]; check.push_back(x); while (x > 0) { y = kmp[x - 1]; check.push_back(y); x = y; } for (int j = 0; j < check.size(); j++) { x = check[j]; if (x > 0) { for (int i = 1; i < (a.length() - 1); i++) { if (kmp[i] == x) { cout << a.substr(0, x); return 0; break; } } } } cout << "Just a legend"; return 0; }
#include <bits/stdc++.h> using namespace std; const double eps = 1e-6; const int N = 1000010; const int INF = 0x3f3f3f3f; const int mod = 1000000007; long long powmod(long long a, long long b) { long long res = 1; a %= mod; assert(b >= 0); for (; b; b >>= 1) { if (b & 1) res = res * a % mod; a = a * a % mod; } return res; } int nxt[2][N]; void preKMP(char x[], int m, int kmpNext[]) { int i = 1, j = kmpNext[1] = 0; while (i <= m) { while (0 != j && x[i + 1] != x[j + 1]) j = kmpNext[j]; if (x[j + 1] == x[i + 1]) ++j; kmpNext[i + 1] = j; ++i; } } int main() { char s[N] = {0}; scanf("%s", s + 1); int len = strlen(s + 1); preKMP(s, len, nxt[0]); reverse(s + 1, s + 1 + len); preKMP(s, len, nxt[1]); reverse(s + 1, s + 1 + len); int pos = 0, mx = 0; for (int i = 1; i <= len; i++) if (nxt[0][i] == nxt[1][len - i + nxt[0][i]]) if (nxt[0][i] > mx) pos = i, mx = nxt[0][i]; if (pos == 0) { cout << "Just a legend" << endl; } else { for (int i = pos - mx + 1; i <= pos; i++) { printf("%c", s[i]); } puts(""); } return 0; }
#include <bits/stdc++.h> using namespace std; char save[1000010]; int pre[1000010]; char tmp[1000010]; int tpre[1000010]; void gpre(char *s, int *p) { int i, j; int len = strlen(s); p[0] = -1; j = -1; for (i = 0; i < len && j < len;) { if (j == -1 || s[i] == s[j]) { p[++i] = ++j; } else { j = p[j]; } } } int find(char *s, char *x, int *p) { int i, j; i = j = 0; int len = strlen(x); int length = strlen(s); while (i < length && j < len) { if (j == -1 || s[i] == x[j]) { i++; j++; } else { j = p[j]; } } if (j == len) { return i - len; } return -1; } int main() { while (scanf("%s", save) != EOF) { gpre(save, pre); int len = strlen(save); if (len == 0) { printf("Just a legend\n"); break; } int e = pre[len]; int res = -1; while (e) { sprintf(tmp, "%s", save + len - e); gpre(tmp, tpre); int tres = find(save + 1, tmp, tpre); if (tres + 1 + e < len) { res = tres + 1; break; } e = pre[e]; } if (res != -1) { printf("%s\n", save + len - e); } else { printf("Just a legend\n"); } } return 0; }
#include <bits/stdc++.h> using namespace std; template <class T, class first> inline bool getbit(T a, first i) { T t = 1; return ((a & (t << i)) > 0); } template <class T, class first> inline T setbit(T a, first i) { T t = 1; return (a | (t << i)); } template <class T, class first> inline T resetbit(T a, first i) { T t = 1; return (a & (~(t << i))); } template <class T, class first> inline T togglebit(T a, first i) { T t = 1; return (a ^ (t << i)); } template <typename T> T POW(T B, T P) { if (P == 0) return 1; if (P & 1) return B * POW(B, P - 1); else return (POW(B, P / 2) * POW(B, P / 2)); } template <typename T> T BIGMOD(T b, T p, T m) { if (p == 0) return 1; else if (!(p & 1)) return (Bigmod(b, p / 2, m) * Bigmod(b, p / 2, m)) % m; else return ((b % m) * Bigmod(b, p - 1, m)) % m; } template <typename T> T Bigmod(T base, T power, T mod) { T ret = 1; while (power) { if (power & 1) ret = (ret * base) % mod; base = (base * base) % mod; power >>= 1; } return ret; } template <typename T> T ModInverse(T number, T mod) { return Bigmod(number, mod - 2, mod); } template <typename T> T GCD(T a, T b) { if (a < 0) return gcd(-a, b); if (b < 0) return gcd(a, -b); return (b == 0) ? a : gcd(b, a % b); } template <typename T> T LCM(T a, T b) { if (a < 0) return lcm(-a, b); if (b < 0) return lcm(a, -b); return a * (b / gcd(a, b)); } template <typename T> T EUCLIDE(T a, T b, T &x, T &y) { if (a < 0) { T d = euclide(-a, b, x, y); x = -x; return d; } if (b < 0) { T d = euclide(a, -b, x, y); y = -y; return d; } if (b == 0) { x = 1; y = 0; return a; } else { T d = euclide(b, a % b, x, y); T t = x; x = y; y = t - (a / b) * y; return d; } } double DEG(double x) { return (180.0 * x) / ((2.0 * acos(0.0))); } double RAD(double x) { return (x * (double)(2.0 * acos(0.0))) / (180.0); } template <typename T> T DIS(T x1, T y1, T x2, T y2) { return sqrt((double)((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2))); } template <typename T> T ANGLE(T x1, T y1, T x2, T y2) { return atan(double(y1 - y2) / double(x1 - x2)); } template <typename T> long long isLeft(T a, T b, T c) { return (c.x - a.x) * (b.y - a.y) - (b.x - a.x) * (c.y - a.y); } void P_ARR(int *ar, int a, int b) { if (a > b) swap(a, b); if (a <= b) cout << ar[a]; for (int i = a + 1; i <= b; i++) cout << " " << ar[i]; cout << endl; } const int MX = 1000007; const int MOD = 1000000007; const int inf = 1000000000; int z_function(int *z, char *s) { int len = strlen(s); for (int i = 0; i <= len; i++) z[i] = 0; z[0] = 0; for (int i = 1, l = 0, r = 0; i < len; ++i) { if (i <= r) z[i] = min(r - i + 1, z[i - l]); while (i + z[i] < len && s[z[i]] == s[i + z[i]]) ++z[i]; if (i + z[i] - 1 > r) l = i, r = i + z[i] - 1; } int mx = -1; int id = -1; for (int i = 1; i <= len - 1; i++) { if (z[i] == len - i && z[i] <= mx) return i; mx = max(mx, z[i]); } return -1; } int main() { int tc, cas = 1; int z[MX]; char s[MX]; gets(s); int st = z_function(z, s); if (st == -1) return puts("Just a legend"); else puts(s + st); return 0; }
#include <bits/stdc++.h> using namespace std; const int MAX = 1000005; char s[MAX]; int z[MAX]; void zfun(int n) { int l = 0, r = 0; for (int i = 1; i < n; ++i) { if (i <= r) z[i] = min(z[i - l], r - i + 1); while (i + z[i] < n && s[i + z[i]] == s[z[i]]) z[i]++; if (i + z[i] - 1 > r) l = i, r = i + z[i] - 1; } } int main() { ios_base::sync_with_stdio(0); cin.tie(0); ; int n; cin >> s; n = strlen(s); zfun(n); int tmp = -1; for (int i = 1; i < n; ++i) { if (z[i] <= tmp && z[i] == n - i) { for (int j = i; j < i + z[i]; ++j) cout << s[j]; return 0; } tmp = max(tmp, z[i]); } cout << "Just a legend" << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 1000100; int nxt[maxn], len; char s[maxn]; set<int> ss; void kmp() { nxt[0] = 0; nxt[1] = 0; for (int i = 1; i < len; ++i) { int k = nxt[i]; while (k && s[k] != s[i]) k = nxt[k]; if (s[k] == s[i]) nxt[i + 1] = k + 1; else nxt[i + 1] = 0; } } int main() { scanf("%s", &s); len = strlen(s); kmp(); for (int i = 0; i < len; ++i) { ss.insert(nxt[i]); } int tem = nxt[len]; while (tem) { if (ss.count(tem)) { for (int i = 0; i < tem; ++i) { printf("%c", s[i]); } return 0; } else { tem = nxt[tem]; } } printf("Just a legend"); return 0; }
#include <bits/stdc++.h> using namespace std; long long int mult(long long int a, long long int b) { return ((a * b) % 1000000007); } long long int pow_m(long long int a, long long int p) { if (p == 0) { return 1; } else if (p == 1) { return a; } long long int temp = pow_m(a, p / 2); if (p % 2 == 0) { return mult(temp, temp); } else { return mult(mult(temp, temp), a); } } long long int inv(long long int a) { if (a == 0) { return 0; } return pow_m(a, 1000000007 - 2); } long long int nChooseK(long long int n, long long int k) { if (k == 0) { return 1; } long long int answer = 1; for (int i = 0; i < k; ++i) { answer = mult(answer, n - i); } for (int i = 2; i <= k; ++i) { answer = mult(answer, inv(i)); } return answer; } long long int nChooseK(long long int n, long long int k, vector<long long int>& pre_mult, vector<long long int>& pre_div) { if (k == 0) { return 1; } long long int answer = 1; answer = mult(answer, pre_mult[n]); answer = mult(answer, pre_div[n - k]); answer = mult(answer, pre_div[k]); return answer; } vector<long long int> coordinate_compression(vector<long long int>& input) { vector<long long int> b = input; sort(b.begin(), b.end()); map<long long int, long long int> mp; for (long long int i = 0; i < b.size(); ++i) { if (mp.find(b[i]) == mp.end()) { mp[b[i]] = i; } } vector<long long int> answer = input; long long int index = 0; while (index < b.size()) { answer[index] = mp[answer[index]]; } return answer; } map<long long int, long long int> get_coordinate_compression_map( vector<long long int>& input) { vector<long long int> b = input; sort(b.begin(), b.end()); map<long long int, long long int> mp; for (long long int i = 0; i < b.size(); ++i) { if (mp.find(b[i]) == mp.end()) { mp[b[i]] = i; } } return mp; } int64_t my_pow(int64_t base, int64_t height) { if (height == 0) { return 1; } if (height % 2 == 0) { int64_t temp = my_pow(base, height / 2); return (temp * temp) % 1000000007; } else { int64_t temp = my_pow(base, height / 2); return ((temp * temp) % 1000000007) * base % 1000000007; } } int main() { ios::sync_with_stdio(0); cin.tie(0); string s; cin >> s; vector<int> dp(s.size(), 0); int n = s.size(); int i = 1; int length = 0; while (i < n) { if (s[i] == s[length]) { dp[i] = length + 1; i++; length++; } else { if (length == 0) { dp[i] = 0; i++; } else { length = dp[length - 1]; } } } if (dp[n - 1] == 0) { cout << "Just a legend\n"; return 0; } string temp = s.substr(0, dp[n - 1]); if (temp.size() + 2 <= s.size()) { int64_t temp_hash = 0; for (int j = 0; j < temp.size(); ++j) { temp_hash = (temp_hash * 26 + (temp[j] - 'a')) % 1000000007; } int64_t current_hash = 0; for (int i = 1; i < temp.size() + 1; ++i) { current_hash = (current_hash * 26 + (s[i] - 'a')) % 1000000007; } if (current_hash == temp_hash) { cout << temp << "\n"; return 0; } for (int i = temp.size() + 1; i < n - 1; ++i) { current_hash = (current_hash + 1000000007 - ((s[i - temp.size()] - 'a') * my_pow(26, temp.size() - 1) % 1000000007)) % 1000000007; current_hash = (current_hash * 26 + (s[i] - 'a')) % 1000000007; if (current_hash == temp_hash && s.substr(i - temp.size() + 1, temp.size()) == temp) { cout << temp << "\n"; return 0; } } } if (dp[dp[n - 1] - 1] == 0) { cout << "Just a legend\n"; return 0; } else { cout << s.substr(0, dp[dp[n - 1] - 1]) << "\n"; } return 0; }
#include <bits/stdc++.h> using namespace std; int main() { string s; cin >> s; int n = s.length(); int i = 1, j = 0; int lps[n]; lps[0] = 0; while (i < n) { if (s[i] == s[j]) { j++; lps[i] = j; i++; } else { if (j != 0) j = lps[j - 1]; else { lps[i] = 0; i++; } } } if (lps[n - 1] == 0) { cout << "Just a legend" << endl; return 0; } for (int i = 0; i < n - 1; i++) { if (lps[i] == lps[n - 1]) { cout << s.substr(0, lps[n - 1]) << endl; return 0; } } if (lps[lps[n - 1] - 1] == 0) cout << "Just a legend" << endl; else cout << s.substr(0, lps[lps[n - 1] - 1]) << endl; }
#include <bits/stdc++.h> using namespace std; const int MN = 1e6 + 44; const int mod = 1e9 + 9, b = 8883; long long rcshnt[MN]; int n; char a[MN]; bool check(int len) { ; long long curr = 0; for (int i = 0; i < len; ++i) curr = (curr * b + a[i]) % mod; long long pre = curr; ; for (int i = len; i < n - 1; ++i) { ; ; curr = ((curr - a[i - len] * rcshnt[len - 1]) % mod * b + a[i]) % mod; ; if ((pre - curr) % mod == 0) { ; return true; } }; return false; } int main() { scanf("%s", a); n = strlen(a); rcshnt[0] = 1; for (int i = 1; i < MN; ++i) { rcshnt[i] = rcshnt[i - 1] * b % mod; } for (int i = 0; i < 10; ++i) ; vector<int> pre; long long ph = 0, sh = 0; for (int i = 0; i < n - 1; ++i) { ph = (ph * b + a[i]) % mod; sh = (sh + a[n - i - 1] * rcshnt[i]) % mod; if (ph == sh) { pre.push_back(i + 1); ; } } int low = 1, high = n - 1, ans = 0; while (low <= high) { int med = (low + high) / 2; if (check(med)) { ans = med; low = med + 1; } else high = med - 1; } int res = -1; for (auto c : pre) { if (c <= ans) res = max(res, c); } if (res <= 0) { printf("Just a legend\n"); } else { a[res] = 0; printf("%s\n", a); } }
#include <bits/stdc++.h> using namespace std; const int MAXN = 1000007; int Z[MAXN]; int cnt[MAXN]; int suff[MAXN]; int main() { ios::sync_with_stdio(false); string s; cin >> s; int L = 0, R = 0; int n = s.size(); Z[0] = n; for (int i = 1; i < n; i++) { if (i > R) { L = i; R = i; } else { int k = i - L; if (Z[k] < R - i + 1) { Z[i] = Z[k]; continue; } else { L = i; } } while (R < n && s[R - L] == s[R]) R++; Z[i] = R - L; R--; } for (int i = 1; i < n; i++) { cnt[Z[i]]++; } for (int i = n - 1; i >= 0; i--) { suff[i] = suff[i + 1] + cnt[i]; } for (int i = 1; i < n; i++) { if (Z[i] + i == n && suff[Z[i]] >= 2) { for (int j = i; j < n; j++) { cout << s[j]; } cout << '\n'; return 0; } } cout << "Just a legend\n"; }
#include <bits/stdc++.h> using namespace std; const int maxn = 1e6 + 10; namespace StrAlgo { vector<int> Kmp(string s) { int n = (int(s.size())); vector<int> ans(n + 1); for (int i = 2; i <= n; i++) { ans[i] = ans[i - 1]; while (ans[i] > 0 && s[ans[i]] != s[i - 1]) ans[i] = ans[ans[i]]; ans[i] += s[ans[i]] == s[i - 1]; } return ans; } vector<int> Z(string s) { int n = (int(s.size())); vector<int> ans(n + 1); int L = -1, R = -1; for (int i = 2; i <= n; i++) { if (i < R) ans[i] = min(ans[i - L + 1], R - i); else L = i, R = i; while (i + ans[i] <= n && s[i - 1 + ans[i]] == s[ans[i]]) ans[i]++; if (i + ans[i] > R) L = i, R = i + ans[i]; } return ans; } }; // namespace StrAlgo void print(string s, int len) { if (len == 0) cout << "Just a legend\n"; else cout << s.substr((int(s.size())) - len) << "\n"; exit(0); } int main() { ios_base::sync_with_stdio(0), cin.tie(), cout.tie(); string s; cin >> s; int n = (int(s.size())); vector<int> z = StrAlgo::Z(s); int ln = 0; for (int i = 2; i <= n; i++) { ln = max(ln, z[i] - (i + z[i] == n + 1)); } for (int i = 2; i <= n; i++) { if (i + z[i] == n + 1 && z[i] <= ln) return cout << s.substr(i - 1) << endl, 0; } return cout << "Just a legend\n", 0; }
#include <bits/stdc++.h> const double eps = 1e-7, PI = 3.1415926; const int N = 2e5 + 10; using namespace std; int n, q, m, k, x, y, a[N], mx = -1, mn = 1e9, sum; char c[N]; string s, s1, s2; map<int, int> mp; vector<int> vec; vector<int> z_function(string s) { int n = (int)s.length(); vector<int> z(n); for (int i = 1, l = 0, r = 0; i < n; ++i) { if (i <= r) z[i] = min(r - i + 1, z[i - l]); while (i + z[i] < n && s[z[i]] == s[i + z[i]]) z[i]++; if (i + z[i] - 1 > r) l = i, r = i + z[i] - 1; } return z; } int main() { cin >> s; vec = z_function(s); int lo = 0; vector<int> op; op = vec; sort(op.begin(), op.end(), greater<int>()); for (int i = 0; i < op.size(); i++) { if (i) mp[op[i]] = mp[op[i - 1]] + 1; else mp[op[i]] = 1; } for (int i = vec.size() - 1; i >= 0; i--) { if (vec[i] && mp[vec[i]] >= 2 && i + vec[i] == vec.size()) lo = vec[i]; } if (lo) { for (int i = 0; i < lo; i++) cout << s[i]; } else { cout << "Just a legend"; } return 0; }
#include <bits/stdc++.h> using namespace std; const int MAX = 1e6 + 5; const unsigned long long seed = 131; unsigned long long Hash[MAX], P[MAX]; char s[MAX]; int n; unsigned long long get(int l, int r) { return Hash[r] - Hash[l - 1] * P[r - l + 1]; } int b[MAX], tot; bool ok(int x) { unsigned long long tar = get(1, x); for (int l = 2; l + x - 1 < n; l++) { int r = l + x - 1; if (tar == get(l, r)) return 1; } return 0; } int main() { cin >> s + 1; n = strlen(s + 1); P[0] = 1; for (int i = 1; i <= n; i++) P[i] = P[i - 1] * seed; for (int i = 1; i <= n; i++) { Hash[i] = Hash[i - 1] * seed + s[i] - 'a' + 1; } for (int i = 1; i <= n; i++) { if (get(1, i) == get(n - i + 1, n)) b[++tot] = i; } int l = 1, r = tot, ans = -1, mid; while (l <= r) { mid = (l + r) >> 1; if (ok(b[mid])) l = mid + 1, ans = b[mid]; else r = mid - 1; } if (ans == -1) { printf("Just a legend\n"); return 0; } for (int i = 1; i <= ans; i++) printf("%c", s[i]); return 0; }
#include <bits/stdc++.h> #pragma GCC optimize("O2") const int MAXN = 1e6 + 5; const int mod = 1e9 + 7; using namespace std; int oc[MAXN]; int main() { ios::sync_with_stdio(0); cin.tie(0); string a; cin >> a; vector<int> f((int)a.size()); int border = 0; f[0] = 0; for (int i = 1; i < (int)a.size(); i++) { while (a[border] != a[i] && border > 0) border = f[border - 1]; if (a[border] == a[i]) border++; f[i] = border; oc[border]++; } if (border && border != (int)a.size() && oc[border] > 1) cout << a.substr(0, border); else if (border && f[border - 1] != 0) cout << a.substr(0, f[border - 1]); else cout << "Just a legend"; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 10; char a[N]; int p[N], n, sxl; int main() { cin >> a + 1; n = strlen(a + 1); p[1] = 0; for (int i = 2, j = 0; i <= n; i++) { while (j && a[i] != a[j + 1]) j = p[j]; if (a[i] == a[j + 1]) j++; p[i] = j; if (i != n) sxl = max(sxl, p[i]); } int x = p[n]; if (x == 0) { cout << "Just a legend"; } else { while (x > sxl) x = p[x]; if (x == 0) { cout << "Just a legend"; return 0; } for (int i = 2; i < n; i++) if (x == p[i]) { for (int j = i - p[i] + 1; j <= i; j++) cout << a[j]; cout << endl; return 0; } } return 0; }
#include <bits/stdc++.h> using namespace std; char text[1000005]; int nxt[1000005]; bool visit[1000005]; void prepare() { int i = 0, j = -1, len = strlen(text); nxt[0] = -1; while (i < len) { if (j == -1 || text[i] == text[j]) { i++; j++; nxt[i] = j; } else { j = nxt[j]; } } } void work() { prepare(); int len = strlen(text); for (int i = 0; i < len; i++) { visit[nxt[i]] = 1; } int pos = len; bool flag = 0; while (nxt[pos] > 0) { if (visit[nxt[pos]]) { flag = 1; for (int i = 0; i < nxt[pos]; i++) cout << text[i]; cout << '\n'; break; } else { pos = nxt[pos]; } } if (!flag) cout << "Just a legend\n"; } int main() { ios::sync_with_stdio(false); cin >> text; work(); }
#include <bits/stdc++.h> using namespace std; long long p = 31; vector<long long> inv_p_powers; long long power(long long a, long long b) { if (b == 0) return 1; long long temp = power(a, b / 2); temp = temp * temp % 1000000007; if (b % 2 == 1) { temp = temp * a % 1000000007; } return temp; } long long find_hash(vector<long long> &prefix_hash, int i, int j) { if (i == 0) return prefix_hash[j]; long long sub_s_hash = (prefix_hash[j] - prefix_hash[i - 1] + 1000000007) % 1000000007; sub_s_hash = sub_s_hash * inv_p_powers[i] % 1000000007; return sub_s_hash; } bool check(string t, int l, vector<long long> &prefix_hash) { int start = 1; int end = start + l - 1; int maxi = prefix_hash.size() - 1; while (1) { if (end >= maxi) break; long long sub_s_hash = find_hash(prefix_hash, start, end); if (sub_s_hash == prefix_hash[l - 1]) return true; start++; end = start + l - 1; } return false; } int main() { int i; long long p_pow = 1; for (i = 1; i <= 1000010; i++) { inv_p_powers.push_back(power(p_pow, 1000000007 - 2)); ; p_pow = p_pow * p % 1000000007; } string t; cin >> t; int len = t.length(); vector<long long> prefix_hash; vector<long long> suffix_hash; long long hash = 0; p_pow = 1; for (i = 0; i <= len - 1; i++) { hash = (hash + p_pow * ((long long)(t[i] - 'a' + 1))) % 1000000007; prefix_hash.push_back(hash); ; p_pow = p_pow * p % 1000000007; } for (i = 0; i <= len - 1; i++) { suffix_hash.push_back(find_hash(prefix_hash, len - 1 - i, len - 1)); ; } vector<int> ans_len; for (i = 0; i <= len - 1; i++) { if (prefix_hash[i] == suffix_hash[i]) { ans_len.push_back(i + 1); ; } } int high = ans_len.size() - 1; int low = 0; while (low < high) { int mid = (low + high + 1) / 2; if (check(t, ans_len[mid], prefix_hash)) { low = mid; } else { high = mid - 1; } } if (check(t, ans_len[low], prefix_hash)) { cout << t.substr(0, ans_len[low]); } else cout << "Just a legend"; return 0; }
#include <bits/stdc++.h> using namespace std; const long double eps = 1e-16; const int MOD = (int)1e9 + 9; const long long INF = (int)1e9 + 10; const int NHASH = 2; template <typename T> vector<T> readVector0(int n) { vector<T> res(n); for (int i = 0; i < n; i++) cin >> res[i]; return res; } template <typename T> vector<T> readVector1(int n) { vector<T> res(n + 1); for (int i = 1; i <= n; i++) cin >> res[i]; return res; } inline long long mod(long long first, long long m = MOD) { if (first < 0) first += m; return (first % m); } template <typename T> bool sortBy2(const pair<T, T> &a, const pair<T, T> &b) { return (a.second < b.second); } int n; vector<long long> p_pow[NHASH]; int p[NHASH]; vector<long long> hp[NHASH]; vector<long long> hs[NHASH]; vector<int> pi; string s; long long binPow(long long a, long long b) { long long res = 1; while (b > 0) { if (b & 1) res = mod(res * a); a = mod(a * a); b >>= 1; } return res; } void getPrefHash(const string &s) { for (int k = 0; k < NHASH; k++) { p_pow[k] = vector<long long>(n); p_pow[k][0] = 1; for (int i = 1; i < n; i++) p_pow[k][i] = (p_pow[k][i - 1] * p[k]) % MOD; hp[k] = vector<long long>(n + 1, 0); for (int i = 0; i < n; i++) hp[k][i + 1] = (hp[k][i] + (s[i] - 'a' + 1) * p_pow[k][i]) % MOD; } } bool checkHashes(const string &s, int i, int j) { for (int k = 0; k < NHASH; k++) { if (mod(hp[k][i] * binPow(p[k], (j - 1))) != hs[k][j]) return false; } return true; } void prefixFunction(const string &s) { for (int i = 1; i < n; i++) { int j = pi[i - 1]; while (j > 0 && s[i] != s[j]) j = pi[j - 1]; if (s[i] == s[j]) j++; pi[i] = j; } } int main() { auto seed = chrono::duration_cast<chrono::nanoseconds>( chrono::steady_clock::now().time_since_epoch()) .count(); mt19937 mt(seed); for (int k = 0; k < NHASH; k++) { p[k] = uniform_int_distribution<int>(31, MOD - 1)(mt); } cin >> s; n = s.size(); pi = vector<int>(n, 0); getPrefHash(s); for (int k = 0; k < NHASH; k++) { hs[k] = vector<long long>(n + 1, 0); for (int i = 1; i <= n; ++i) hs[k][i] = (hp[k][n] - hp[k][i - 1] + MOD) % MOD; } prefixFunction(s); int m_l = 0; for (int i = 0; i < n - 1; ++i) { if (pi[i] > m_l && checkHashes(s, pi[i], n + 1 - pi[i])) { m_l = pi[i]; } } if (m_l == 0) { cout << "Just a legend"; return 0; } cout << s.substr(0, m_l); return 0; }
#include <bits/stdc++.h> using namespace std; const int MN = 1e6 + 44; const int mod = 1e9 + 9, b = 1418; long long rcshnt[MN]; int n; char a[MN]; bool check(int len) { ; long long curr = 0; for (int i = 0; i < len; ++i) curr = (curr * b + a[i]) % mod; long long pre = curr; ; for (int i = len; i < n - 1; ++i) { ; ; curr = ((curr - a[i - len] * rcshnt[len - 1]) % mod * b + a[i]) % mod; ; if ((pre - curr) % mod == 0) { ; return true; } }; return false; } int main() { scanf("%s", a); n = strlen(a); rcshnt[0] = 1; for (int i = 1; i < MN; ++i) { rcshnt[i] = rcshnt[i - 1] * b % mod; } for (int i = 0; i < 10; ++i) ; vector<int> pre; long long ph = 0, sh = 0; for (int i = 0; i < n - 1; ++i) { ph = (ph * b + a[i]) % mod; sh = (sh + a[n - i - 1] * rcshnt[i]) % mod; if (ph == sh) { pre.push_back(i + 1); ; } } int low = 1, high = n - 1, ans = 0; while (low <= high) { int med = (low + high) / 2; if (check(med)) { ans = med; low = med + 1; } else high = med - 1; } int res = -1; for (auto c : pre) { if (c <= ans) res = max(res, c); } if (res <= 0) { printf("Just a legend\n"); } else { a[res] = 0; printf("%s\n", a); } }
#include <bits/stdc++.h> using namespace std; string a; bool kmp(string s) { vector<int> v; v.resize(s.size()); v[0] = 0; for (int i = 1, j = 0; i < s.size(); ++i) { if (s[i] == s[j]) { v[i] = j + 1; ++j; } else { if (j == 0) ; else { j = v[j - 1]; --i; } } } string str = s.substr(0, v[v.size() - 1]); v.resize(str.size()); v[0] = 0; for (int i = 1, j = 0; i < str.size(); ++i) { if (str[i] == str[j]) { v[i] = j + 1; ++j; } else { if (j == 0) ; else { j = v[j - 1]; --i; } } } if (str.size() == 0) return false; int k = 0; int ans = 0; for (int i = 0; i < a.size(); ++i) { if (a[i] == str[k]) { ++k; if (k == str.size()) { ++ans; if (k > 0) k = v[k - 1]; } } else { if (k > 0) { k = v[k - 1]; --i; } } } if (ans > 2) { cout << str; return true; } return kmp(str); } int main() { cin >> a; if (!kmp(a)) cout << "Just a legend"; }
#include <bits/stdc++.h> using namespace std; void task() { string str; cin >> str; int l = 0; int r = 0; vector<int> z(str.length(), 0); for (int i = 1; i < str.length(); i++) { if (r > i) { z[i] = min(z[i - l], r - i); } while (i + z[i] < str.length() && str[z[i]] == str[i + z[i]]) { z[i]++; } if (i + z[i] > r) { l = i; r = i + z[i]; } } int maxlen = -1; int ans = -1; for (int i = 0; i < str.length() && ans == -1; i++) { if (z[i] != 0) { if (i + z[i] == str.length() && maxlen >= z[i]) { ans = z[i]; } else { maxlen = max(z[i], maxlen); } } } if (ans == -1) { cout << "Just a legend" << endl; } for (int i = str.length() - ans; i < str.length(); i++) { cout << str[i]; } cout << endl; } int main() { ios::sync_with_stdio(false); cin.tie(NULL); task(); return 0; }
#include <bits/stdc++.h> char in[1100000]; unsigned long long hs, st[1100000], ed[1100000]; unsigned long long pw[1100000]; int main() { int i, j, k, l, m, n, ok, res; while (scanf("%s", in) == 1) { n = strlen(in); res = 0; pw[0] = 1; for (i = 0; i < n + 1; i++) pw[i + 1] = pw[i] * 10007; st[0] = ed[0] = 0; for (i = 0; i < n; i++) st[i + 1] = st[i] * 10007 + in[i]; for (i = 0; i < n; i++) ed[i + 1] = ed[i] + in[n - 1 - i] * pw[i]; for (k = n - 1; k; k--) if (st[k] == ed[k]) { ok = 0; hs = 0; for (i = 0; i < k; i++) hs = hs * 10007 + in[i]; for (i = k; i < n - 1; i++) { hs = hs * 10007 + in[i] - in[i - k] * pw[k]; if (hs == st[k]) ok = 1; } if (ok) { res = k; break; } } if (res > 0) { for (i = 0; i < res; i++) putchar(in[i]); puts(""); } else { puts("Just a legend"); } } return 0; }
#include <bits/stdc++.h> #pragma GCC optimize("O3") const int inf = 0x3f3f3f3f; template <typename T> T gcd(T a, T b) { if (a == 0) return b; return gcd(b % a, a); } long long power(long long a, long long b, long long m = 1000000007) { long long answer = 1; while (b) { if (b & 1) answer = (answer * a) % m; b /= 2; a = (a * a) % m; } return answer; } using namespace std; vector<int> z_function(string second) { int n = (int)second.length(); vector<int> z(n); for (int i = 1, l = 0, r = 0; i < n; ++i) { if (i <= r) z[i] = min(r - i + 1, z[i - l]); while (i + z[i] < n && second[z[i]] == second[i + z[i]]) ++z[i]; if (i + z[i] - 1 > r) l = i, r = i + z[i] - 1; } return z; } int pi[1000000 + 5]; void kmpPreprocess(string &P) { int i = 0, j = -1, m = P.size(); pi[0] = -1; while (i < m) { while (j >= 0 and P[i] != P[j]) j = pi[j]; i++, j++; pi[i] = j; } } int main() { string p; cin >> p; vector<int> z; z = z_function(p); kmpPreprocess(p); int mx = 0; string h = ""; int n = p.length(); bool flag = true; if (pi[n] == 0) { cout << "Just a legend\n"; return 0; } for (int i = 0; i < n; i++) { if (pi[n] == pi[i]) { for (int j = 0; j < pi[i]; j++) cout << p[j]; return 0; } } if (pi[pi[n]] == 0) { cout << "Just a legend\n"; return 0; } for (int i = 0; i < pi[pi[n]]; i++) cout << p[i]; return 0; }
#include <bits/stdc++.h> using namespace std; const int NMAX = 1000000; string s; vector<int> pi; int main() { getline(cin, s); int n = s.size(); s.insert(s.begin(), 0); pi.push_back(0); pi.push_back(0); for (int i = 2, k = 0; i <= n; ++i) { while (k > 0 && s[i] != s[k + 1]) k = pi[k]; pi.push_back(k += int(s[i] == s[k + 1])); } int p = pi[n]; bool b = false; while (p) { int i; for (i = p + 1; i < n; ++i) if (pi[i] == p) break; if (i < n) { cout << s.substr(1, p); b = true; break; } else p = pi[p]; } if (!b) cout << "Just a legend\n"; return 0; }
#include <bits/stdc++.h> using namespace std; const int MAX = 1000007; string s; int pi[MAX]; char p[MAX], p2[MAX], T; void compute_prefix_function(int m) { int k = pi[0] = -1; for (int i = 1; i < m; i++) { while (k >= 0 && s[i] != s[k + 1]) k = pi[k]; if (s[i] == s[k + 1]) k++; pi[i] = k; } } int main() { cin >> s; compute_prefix_function(s.size()); int ans = pi[s.size() - 1]; if (ans == -1) { cout << "Just a legend\n"; return 0; } for (int i = 1; i < s.size() - 1; i++) { if (ans == pi[i]) { cout << s.substr(0, ans + 1) << '\n'; return 0; } } ans = pi[ans]; if (ans == -1) cout << "Just a legend\n"; else cout << s.substr(0, ans + 1) << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000007; int phi[N]; void build(string& s) { phi[0] = 0; for (int i = 1; i < s.size(); i++) { int j = phi[i - 1]; while (j and s[i] != s[j]) j = phi[j - 1]; if (s[i] == s[j]) phi[i] = j + 1; else phi[i] = 0; } } int main() { string s; cin >> s; build(s); int bestmid = 0; for (int i = 1; i < s.size() - 1; i++) bestmid = max(bestmid, phi[i]); int j = phi[s.size() - 1]; while (j > bestmid) j = phi[j - 1]; if (!j) cout << "Just a legend\n"; else cout << s.substr(0, j) << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; int a[1000008]; int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); string s; cin >> s; a[0] = 0; int i = 1, l = 0, n = s.length(); while (i < n) { if (s[i] == s[l]) { l++; a[i] = l; i++; } else { if (l != 0) { l = a[l - 1]; } else { a[i] = 0; i++; } } } if (a[n - 1] == 0) { cout << "Just a legend\n"; return 0; } for (int i = 1; i <= n - 2; i++) { if (a[i] == a[n - 1]) { for (int i = 0; i < a[n - 1]; i++) { cout << s[i]; } return 0; } } if (a[a[n - 1] - 1] == 0) { cout << "Just a legend\n"; return 0; } for (int i = 1; i <= n - 2; i++) { if (a[i] == a[a[n - 1] - 1]) { for (int i = 0; i < a[a[n - 1] - 1]; i++) { cout << s[i]; } return 0; } } cout << "Just a legend"; return 0; }
#include <bits/stdc++.h> using namespace std; const int MAX_N = 1000005; int main() { char s[MAX_N]; scanf("%s", s); int n = strlen(s); vector<int> z(n + 1); int l = 0, r = 0; z[0] = 0; for (int i = 1; i < n; ++i) { if (i <= r) z[i] = min(r - i + 1, z[i - l]); while (z[i] + i < n && s[z[i] + i] == s[z[i]]) ++z[i]; if (i + z[i] - 1 > r) r = i + z[i] - 1, l = i; } set<int> substr; vector<char> good_pr(n + 1, 0); for (int i = 1; i < n; ++i) { if (i + z[i] >= n) { good_pr[z[i]] = 1; substr.insert(z[i] - 1); } else { substr.insert(z[i]); } } int res = 0; for (int i = 1; i <= n; ++i) { if (good_pr[i] && substr.lower_bound(i) != substr.end()) res = max(res, i); } if (res == 0) { printf("Just a legend"); } else { for (int i = 0; i < res; ++i) printf("%c", s[i]); } return 0; }
#include <bits/stdc++.h> using namespace std; template <class T, class first> inline bool getbit(T a, first i) { T t = 1; return ((a & (t << i)) > 0); } template <class T, class first> inline T setbit(T a, first i) { T t = 1; return (a | (t << i)); } template <class T, class first> inline T resetbit(T a, first i) { T t = 1; return (a & (~(t << i))); } template <class T, class first> inline T togglebit(T a, first i) { T t = 1; return (a ^ (t << i)); } template <typename T> T POW(T B, T P) { if (P == 0) return 1; if (P & 1) return B * POW(B, P - 1); else return (POW(B, P / 2) * POW(B, P / 2)); } template <typename T> T BIGMOD(T b, T p, T m) { if (p == 0) return 1; else if (!(p & 1)) return (Bigmod(b, p / 2, m) * Bigmod(b, p / 2, m)) % m; else return ((b % m) * Bigmod(b, p - 1, m)) % m; } template <typename T> T Bigmod(T base, T power, T mod) { T ret = 1; while (power) { if (power & 1) ret = (ret * base) % mod; base = (base * base) % mod; power >>= 1; } return ret; } template <typename T> T ModInverse(T number, T mod) { return Bigmod(number, mod - 2, mod); } template <typename T> T GCD(T a, T b) { if (a < 0) return gcd(-a, b); if (b < 0) return gcd(a, -b); return (b == 0) ? a : gcd(b, a % b); } template <typename T> T LCM(T a, T b) { if (a < 0) return lcm(-a, b); if (b < 0) return lcm(a, -b); return a * (b / gcd(a, b)); } template <typename T> T EUCLIDE(T a, T b, T &x, T &y) { if (a < 0) { T d = euclide(-a, b, x, y); x = -x; return d; } if (b < 0) { T d = euclide(a, -b, x, y); y = -y; return d; } if (b == 0) { x = 1; y = 0; return a; } else { T d = euclide(b, a % b, x, y); T t = x; x = y; y = t - (a / b) * y; return d; } } double DEG(double x) { return (180.0 * x) / ((2.0 * acos(0.0))); } double RAD(double x) { return (x * (double)(2.0 * acos(0.0))) / (180.0); } template <typename T> T DIS(T x1, T y1, T x2, T y2) { return sqrt((double)((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2))); } template <typename T> T ANGLE(T x1, T y1, T x2, T y2) { return atan(double(y1 - y2) / double(x1 - x2)); } template <typename T> long long isLeft(T a, T b, T c) { return (c.x - a.x) * (b.y - a.y) - (b.x - a.x) * (c.y - a.y); } void P_ARR(int *ar, int a, int b) { if (a > b) swap(a, b); if (a <= b) cout << ar[a]; for (int i = a + 1; i <= b; i++) cout << " " << ar[i]; cout << endl; } const int MX = 1000007; const int MOD = 1000000007; const int inf = 1000000000; int z[MX]; char s[MX]; int z_function() { int len = strlen(s); z[0] = 0; for (int i = 1, l = 0, r = 0; i < len; ++i) { if (i <= r) z[i] = min(r - i + 1, z[i - l]); while (i + z[i] < len && s[z[i]] == s[i + z[i]]) ++z[i]; if (i + z[i] - 1 > r) l = i, r = i + z[i] - 1; } int mx = -1; int id = -1; for (int i = 1; i <= len - 1; i++) { if (z[i] == len - i && z[i] <= mx) return i; mx = max(mx, z[i]); } return -1; } int main() { int tc, cas = 1; gets(s); int st = z_function(); if (st == -1) return puts("Just a legend"); else puts(s + st); return 0; }
#include <bits/stdc++.h> using namespace std; const char nl = '\n'; const int mod = 1000000007; const double pi = 4 * atan(1); const int inf = 2000000000; const long long linf = (long long)1e18; const int pr = 37; const int maxn = 1000001; const int maxn_big = 1000001; string s; vector<int> v; unsigned long long h[maxn], p[maxn]; unsigned long long get_hash(int l, int r) { int len = (r - l) + 1; if (!l) return h[r]; return h[r] - h[l - 1] * p[len]; } bool check(int pf) { unsigned long long pref_hash = get_hash(0, pf); bool has_ans = 0; for (int i = 1; i < ((int)(s.size())) - 1; ++i) { int r = i + pf; if (r >= ((int)(s.size())) - 1) break; if (get_hash(i, r) == pref_hash) { has_ans = 1; break; } } return has_ans; } int main() { ios_base ::sync_with_stdio(0); cin.tie(0); srand(time(NULL)); cin >> s; h[0] = s[0]; p[0] = 1; for (int i = 1; i < ((int)(s.size())); ++i) { h[i] = h[i - 1] * pr + s[i]; p[i] = p[i - 1] * pr; } for (int i = 0; i < ((int)(s.size())); ++i) { int l = ((int)(s.size())) - 1 - i; if (get_hash(0, i) == get_hash(l, ((int)(s.size())) - 1)) v.push_back(i); } if (!((int)(v.size()))) { cout << "Just a legend"; return 0; } int l = -1, r = ((int)(v.size())); bool has = 0; while (r - l > 1) { int mid = (r + l) / 2; if (check(v[mid])) { l = mid; has = 1; } else { r = mid; } } if (!has) { cout << "Just a legend"; return 0; } string res = ""; for (int i = 0; i <= v[l]; ++i) res += s[i]; cout << res; return 0; }
#include <bits/stdc++.h> using namespace std; const int MN = 1e6 + 44; const int mod = 1e9 + 9, b = 8113; long long rcshnt[MN]; int n; char a[MN]; bool check(int len) { ; long long curr = 0; for (int i = 0; i < len; ++i) curr = (curr * b + a[i]) % mod; long long pre = curr; ; for (int i = len; i < n - 1; ++i) { ; ; curr = ((curr - a[i - len] * rcshnt[len - 1]) % mod * b + a[i]) % mod; ; if ((pre - curr) % mod == 0) { ; return true; } }; return false; } int main() { scanf("%s", a); n = strlen(a); rcshnt[0] = 1; for (int i = 1; i < MN; ++i) { rcshnt[i] = rcshnt[i - 1] * b % mod; } for (int i = 0; i < 10; ++i) ; vector<int> pre; long long ph = 0, sh = 0; for (int i = 0; i < n - 1; ++i) { ph = (ph * b + a[i]) % mod; sh = (sh + a[n - i - 1] * rcshnt[i]) % mod; if (ph == sh) { pre.push_back(i + 1); ; } } int low = 1, high = n - 1, ans = 0; while (low <= high) { int med = (low + high) / 2; if (check(med)) { ans = med; low = med + 1; } else high = med - 1; } int res = -1; for (auto c : pre) { if (c <= ans) res = max(res, c); } if (res <= 0) { printf("Just a legend\n"); } else { a[res] = 0; printf("%s\n", a); } }
#include <bits/stdc++.h> using namespace std; const long long maxsz = 1e6 + 10; char s[maxsz]; const long long p1 = 1e9 + 321; const long long base = 1013; long long pws1[maxsz]; long long preff[maxsz]; void build(long long len) { pws1[0] = 1; preff[0] = 0; for (int i = 1; i <= len; i++) { pws1[i] = (pws1[i - 1] * base) % p1; preff[i] = (preff[i - 1] * base + (s[i - 1] - 'a' + 1)) % p1; } } long long getKey(long long l, long long r) { long long len = r - l + 1; long long res = (preff[l + len] - preff[l] * pws1[len]) % p1; if (res < 0) res += p1; return res; } bool isSame(long long len, long long len_str) { long long num1 = getKey(0, len - 1); long long inv_l = len_str - len; long long num2 = getKey(inv_l, len_str - 1); if (num1 == num2) return true; return false; } vector<long long> nums; bool find_str(long long hash_num, long long len, long long len_str) { for (int L = 1; L + len < len_str; L++) { long long R = L + len - 1; long long num1 = getKey(L, R); if (num1 == hash_num) return true; } return false; } int main() { scanf("%s", s); long long len = strlen(s); build(len); for (int r = 1; r < len - 1; r++) { if (isSame(r, len)) nums.push_back(r); } long long lo = 0, hi = nums.size(); long long p = -1; while (lo < hi) { long long mi = (lo + hi) / 2; long long tst = nums[mi]; long long prf = getKey(0, tst - 1); if (find_str(prf, tst, len)) lo = mi + 1, p = max(tst, p); else hi = mi; } if (p != -1) for (int i = 0; i < p; i++) cout << s[i]; else cout << "Just a legend"; cout << endl; }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 5; char s[N]; int n, z[N]; map<int, int> cnt; void Z_function() { int L = 0, R = 0; z[1] = n; for (int i = 2; i <= n; i++) { if (i > R) { L = R = i; while (R <= n && s[R] == s[R - L + 1]) R++; z[i] = R - L; R--; } else { int k = i - L + 1; if (z[k] < R - i + 1) z[i] = z[k]; else { L = i; while (R <= n && s[R] == s[R - L + 1]) R++; z[i] = R - L; R--; } } } } int main() { scanf("%s", s + 1); n = strlen(s + 1); Z_function(); for (int i = 1; i <= n; i++) cnt[z[i]]++; for (int i = n; i >= 1; i--) cnt[i] += cnt[i + 1]; int ans = -1; for (int i = n; i >= 2; i--) { if (z[i] == n - i + 1 && cnt[z[i]] >= 3) ans = i; } if (ans == -1) puts("Just a legend"); else { for (int i = ans; i <= n; i++) printf("%c", s[i]); } }
#include <bits/stdc++.h> using namespace std; string s; int p[1000001]; map<int, bool> used; int main() { cin >> s; for (int i = 1; i < s.size(); ++i) { int j = p[i - 1]; while (j > 0 && s[j] != s[i]) j = p[j - 1]; if (s[i] == s[j]) ++j; p[i] = j; if (i != s.size() - 1) used[p[i]] = true; } int j = p[s.size() - 1]; while (j > 0) { if (used[j]) { for (int i = 0; i < j; ++i) cout << s[i]; return 0; } j = p[j - 1]; } cout << "Just a legend" << endl; }
#include <bits/stdc++.h> using namespace std; namespace IO { template <typename T> void __RI(T &x) { int ch = getchar(), neg = 1; x = 0; for (; !(isdigit(ch) || ch == '-' || ch == EOF); ch = getchar()) ; if (ch == EOF) return; if (ch == '-') neg = -1, ch = getchar(); for (; isdigit(ch); ch = getchar()) x = x * 10 + ch - 48; x *= neg; } void R(int &x) { __RI(x); } void R(int64_t &x) { __RI(x); } template <typename T1, typename T2> void R(std::pair<T1, T2> &x) { R(x.first); R(x.second); } template <typename T> void R(std::vector<T> &x) { for (auto &i : x) { R(i); } } template <typename T> void R(T &x) { std::cin >> x; } template <typename T, typename... Args> void R(T &x, Args &...args) { R(x), R(args...); } template <typename T> void RA(T *arr, int l, int r) { arr += l; int p = r - l + 1; while (p--) R(*arr++); } char space = ' '; template <typename T> void __WI(T x) { if (x == 0) putchar('0'); if (x < 0) putchar('-'), x = -x; char ch[64]; int pos = 0; while (x) ch[pos++] = x % 10 + 48, x /= 10; while (pos) putchar(ch[--pos]); } void W() {} void W(const int &x) { __WI(x); } void W(const int64_t &x) { __WI(x); } void W(const double &x) { printf("%lf", static_cast<double>(x)); } void W(const char &x) { putchar(x); } void W(const std::string &x) { printf("%s", x.c_str()); } template <typename T1, typename T2> void W(const std::pair<T1, T2> &x) { W(x.first); W(space); W(x.second); } template <typename T> void W(const std::vector<T> &x) { for (auto it = x.cbegin(); it != x.cend(); it++) { W(*it); W(space); } W('\n'); } template <typename T> void W(const T &x) { std::cout << x; } template <typename T, typename... Args> void W(const T &x, const Args &...args) { W(x), W(space), W(args...); } template <typename... Args> void WL(const Args &...args) { W(args...), W('\n'); } template <typename T> void WA(T *arr, int l, int r, char sp = ' ') { arr += l; int p = r - l; while (p--) W(*arr++), W(sp); W(*arr); } template <typename T> void WAL(T *arr, int l, int r) { arr += l; int p = r - l; while (p--) W(*arr++); WL(*arr); } }; // namespace IO char t[1000010]; int nxt[1000010], vis[1000010]; int len; void getnxt() { nxt[0] = -1; int i = 0, j = -1; while (i < len) { if (j == -1 || t[i] == t[j]) i++, j++, nxt[i] = j; else j = nxt[j]; } for (int i = 0; i < len; i++) vis[nxt[i]]++; } int main() { IO::R(t); len = strlen(t); getnxt(); int j = len; bool ok = 0; while (nxt[j] != 0) { if (vis[nxt[j]]) { IO::WAL(t, 0, nxt[j] - 1); ok = 1; break; } j = nxt[j]; } if (ok == 0) IO::WL("Just a legend"); return 0; }
#include <bits/stdc++.h> char str[1000005]; int z[1000005]; int len, answer; void CalcZArrayN2() { for (int i = 1; i < len; i++) { while ((i + z[i] < len) && (str[i + z[i]] == str[z[i]])) { z[i]++; } } } inline int max(int a, int b) { return a > b ? a : b; } inline int min(int a, int b) { return a < b ? a : b; } void CalcZArrayLinear() { int l = 0, r = 0; for (int i = 1; i < len; i++) { if (i <= r) { z[i] = min(r - i + 1, z[i - l]); } while ((i + z[i] < len) && (str[i + z[i]] == str[z[i]])) { z[i]++; } if (i + z[i] - 1 > r) { l = i; r = i + z[i] - 1; } } } void ReadData() { memset(str, 0, sizeof(char) * 1000005); memset(z, 0, sizeof(int) * 1000005); scanf("%s\n", &str); } void Solve() { len = strlen(str); answer = -1; if (len < 3) return; CalcZArrayLinear(); int maxz = 0; for (int i = 1; i < len; i++) { if (z[i] == len - i && maxz >= len - i) { answer = len - i; break; } maxz = max(maxz, z[i]); } } void WriteData() { if (answer == -1) { printf("Just a legend"); } else { for (int i = 0; i < answer; i++) { printf("%c", str[i]); } } printf("\n"); } int main() { int QWE; QWE = 1; for (int T = 0; T < QWE; T++) { ReadData(); Solve(); WriteData(); } return 0; }
#include <bits/stdc++.h> #pragma GCC optimize("Ofast") #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,fma") #pragma GCC optimize("unroll-loops") using namespace std; const double eps = 1e-12; const long long MOD = 1e9 + 7; const double PI = acos(-1.0); const long long INF = 1e18; vector<long long> z_function(string &s) { long long n = (long long)s.length(); vector<long long> z(n); for (long long i = 1, l = 0, r = 0; i < n; ++i) { if (i <= r) z[i] = min(r - i + 1, z[i - l]); while (i + z[i] < n && s[z[i]] == s[i + z[i]]) ++z[i]; if (i + z[i] - 1 > r) l = i, r = i + z[i] - 1; } return z; } void solve() { string s; cin >> s; long long n = s.length(); if (n == 1) { cout << "Just a legend\n"; return; } vector<long long> z = z_function(s); map<long long, pair<long long, long long>, greater<long long>> m; for (long long i = 1; i < n; i++) { pair<long long, long long> p = {m[z[i]].first + 1, i}; m[z[i]] = p; } long long take = 0; for (auto x : m) { take += x.second.first; if (take >= 2) { if (z[x.second.second] + x.second.second == n) { cout << s.substr(0, x.first) << "\n"; return; } } } cout << "Just a legend\n"; } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); ; long long t = 1; while (t--) { solve(); } return 0; }
#include <bits/stdc++.h> using namespace std; constexpr const long long MOD = 1e9 + 7; string solve(const string &inp) { string zstr = inp; vector<int> z(zstr.length()); set<int, greater<int>> suffix; int limit = 0; for (int i = 1, l = 0, r = 0; i < z.size(); ++i) { auto prefix_candidate = z[i - l] < r - i + 1 ? z[i - l] : r - i + 1; z[i] = 0 > prefix_candidate ? 0 : prefix_candidate; while (z[i] + i < zstr.length() && zstr[z[i]] == zstr[z[i] + i]) l = i, r = z[i] + i, ++z[i]; if (z[i] + i == zstr.length()) { suffix.insert(z[i]); limit = z[i] - 1 > limit ? z[i] - 1 : limit; } else limit = z[i] > limit ? z[i] : limit; } auto it = suffix.begin(); for (; it != suffix.end() && (*it > limit); ++it) ; if (it != suffix.end() && *it > 0) return inp.substr(0, *it); return "Just a legend"; } int main() { ios_base::sync_with_stdio(false); cin.tie(0); string inp; cin >> inp; cout << solve(inp) << "\n"; return 0; }
#include <bits/stdc++.h> const long long ary = 1e6 + 5; const long long mod = 1e9 + 7; const long long inf = 1e18; using namespace std; string second; long long z[ary], c[ary], mx; void zf() { long long l = 1, r = 1; for (int i = 1; i < (long long)second.size(); i++) { z[i] = max(0ll, min(z[i - l], r - i + 1)); c[z[i]]++; while (i + z[i] < (long long)second.size() && second[z[i]] == second[i + z[i]]) { z[i]++; c[z[i]]++; } if (i + z[i] - 1 > r) { l = i; r = i + z[i] - 1; } } } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> second; zf(); for (int i = 0; i < (long long)second.size(); i++) { if (i + z[i] == (long long)second.size()) { if (c[z[i]] > 1) { for (int j = i; j < i + z[i]; j++) { cout << second[j]; } return 0; } } } cout << "Just a legend"; }
#include <bits/stdc++.h> using namespace std; using ll = long long; using VI = vector<ll>; using VB = vector<bool>; using VD = vector<long double>; using VC = vector<char>; using VS = vector<string>; using VPII = vector<pair<ll, ll> >; using V2I = vector<VI>; using V3I = vector<V2I>; const ll mod{(ll)1e9 + 7}; const ll mod2{(ll)1e9 + 9}; const long double pi = 2 * acos(0.0); const ll INF{(ll)1e14}; void godSpeed(); ll gcdExtended(ll a, ll b, ll &x, ll &y) { if (a == 0) { x = 0; y = 1; return b; } ll x1, y1; ll d = gcdExtended(b % a, a, x1, y1); x = y1 - (b / a) * x1; y = x1; return d; } ll modInverse(ll a, ll m = mod) { ll x, y; ll d = gcdExtended(a, m, x, y); if (d != 1) { return -1; } return (x % m + m) % mod; } const ll p{31LL}; ll pwr1[(ll)1e6 + 5]; ll pow1[(ll)1e6 + 5]; void preCalc(ll n, ll mod) { ll total{1LL}; for (ll i{0}; i < n; ++i) { pow1[i] = total; pwr1[i] = modInverse(total, mod); total = total * p % mod; } } void solve() { string s; cin >> s; ll n{(ll)s.size()}; preCalc(n, mod); ll preSum[(ll)1e6 + 5]; ll hash_val1{}; for (ll i{0}; i < n; ++i) { hash_val1 = (hash_val1 + (s[i] - 'a' + 1) * pow1[i]) % mod; preSum[i] = hash_val1; } VI vec; for (ll i{0}; i < n - 1; ++i) { ll tem1{(preSum[n - 1] - preSum[i] + mod) % mod}; tem1 = tem1 * pwr1[i + 1] % mod; ll pr{tem1}; if (preSum[n - 2 - i] == pr) vec.push_back({n - i - 1}); } sort(vec.begin(), vec.end()); ll st{}, en{(ll)vec.size() - 1}; while (st <= en) { ll mid{(st + en) / 2}, len{vec[mid]}; auto pr{preSum[len - 1]}; bool find{}; for (ll i{1}; i < n - len; i++) { ll val{}; val = (preSum[i + len - 1] - preSum[i - 1] + mod) % mod; val = val * pwr1[i] % mod; if (pr == val) { find = 1; break; } } if (find) st = mid + 1; else en = mid - 1; } if (en < 0) cout << "Just a legend"; else cout << s.substr(0, vec[en]); } int32_t main() { godSpeed(); solve(); } void godSpeed() { ios::sync_with_stdio(0); cin.tie(0); }
#include <bits/stdc++.h> using namespace std; const int MN = 1e6 + 44; const int mod = 1e9 + 9, b = 7771; long long rcshnt[MN]; int n; char a[MN]; bool check(int len) { ; long long curr = 0; for (int i = 0; i < len; ++i) curr = (curr * b + a[i]) % mod; long long pre = curr; ; for (int i = len; i < n - 1; ++i) { ; ; curr = ((curr - a[i - len] * rcshnt[len - 1]) % mod * b + a[i]) % mod; ; if ((pre - curr) % mod == 0) { ; return true; } }; return false; } int main() { scanf("%s", a); n = strlen(a); rcshnt[0] = 1; for (int i = 1; i < MN; ++i) { rcshnt[i] = rcshnt[i - 1] * b % mod; } for (int i = 0; i < 10; ++i) ; vector<int> pre; long long ph = 0, sh = 0; for (int i = 0; i < n - 1; ++i) { ph = (ph * b + a[i]) % mod; sh = (sh + a[n - i - 1] * rcshnt[i]) % mod; if (ph == sh) { pre.push_back(i + 1); ; } } int low = 1, high = n - 1, ans = 0; while (low <= high) { int med = (low + high) / 2; if (check(med)) { ans = med; low = med + 1; } else high = med - 1; } int res = -1; for (auto c : pre) { if (c <= ans) res = max(res, c); } if (res <= 0) { printf("Just a legend\n"); } else { a[res] = 0; printf("%s\n", a); } }
#include <bits/stdc++.h> using namespace std; const int MN = 1e6 + 44; const int mod = 1e9 + 9, b = 12388; long long rcshnt[MN]; int n; char a[MN]; bool check(int len) { ; long long curr = 0; for (int i = 0; i < len; ++i) curr = (curr * b + a[i]) % mod; long long pre = curr; ; for (int i = len; i < n - 1; ++i) { ; ; curr = ((curr - a[i - len] * rcshnt[len - 1]) % mod * b + a[i]) % mod; ; if ((pre - curr) % mod == 0) { ; return true; } }; return false; } int main() { scanf("%s", a); n = strlen(a); rcshnt[0] = 1; for (int i = 1; i < MN; ++i) { rcshnt[i] = rcshnt[i - 1] * b % mod; } for (int i = 0; i < 10; ++i) ; vector<int> pre; long long ph = 0, sh = 0; for (int i = 0; i < n - 1; ++i) { ph = (ph * b + a[i]) % mod; sh = (sh + a[n - i - 1] * rcshnt[i]) % mod; if (ph == sh) { pre.push_back(i + 1); ; } } int low = 1, high = n - 1, ans = 0; while (low <= high) { int med = (low + high) / 2; if (check(med)) { ans = med; low = med + 1; } else high = med - 1; } int res = -1; for (auto c : pre) { if (c <= ans) res = max(res, c); } if (res <= 0) { printf("Just a legend\n"); } else { a[res] = 0; printf("%s\n", a); } }
#include <bits/stdc++.h> using namespace std; const int MN = 1e6 + 44; const int mod = 1e9 + 9, b = 12387; long long rcshnt[MN]; int n; char a[MN]; bool check(int len) { ; long long curr = 0; for (int i = 0; i < len; ++i) curr = (curr * b + a[i]) % mod; long long pre = curr; ; for (int i = len; i < n - 1; ++i) { ; ; curr = ((curr - a[i - len] * rcshnt[len - 1]) % mod * b + a[i]) % mod; ; if ((pre - curr) % mod == 0) { ; return true; } }; return false; } int main() { scanf("%s", a); n = strlen(a); rcshnt[0] = 1; for (int i = 1; i < MN; ++i) { rcshnt[i] = rcshnt[i - 1] * b % mod; } for (int i = 0; i < 10; ++i) ; vector<int> pre; long long ph = 0, sh = 0; for (int i = 0; i < n - 1; ++i) { ph = (ph * b + a[i]) % mod; sh = (sh + a[n - i - 1] * rcshnt[i]) % mod; if (ph == sh) { pre.push_back(i + 1); ; } } int low = 1, high = n - 1, ans = 0; while (low <= high) { int med = (low + high) / 2; if (check(med)) { ans = med; low = med + 1; } else high = med - 1; } int res = -1; for (auto c : pre) { if (c <= ans) res = max(res, c); } if (res <= 0) { printf("Just a legend\n"); } else { a[res] = 0; printf("%s\n", a); } }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 6; int p[N]; void kmp(string s) { int n = s.length(); for (int i = 1; i < n; i++) { int j = p[i - 1]; while (j > 0 && s[i] != s[j]) j = p[j - 1]; if (s[i] == s[j]) j++; p[i] = j; } } int main() { ios_base::sync_with_stdio(false); string s; cin >> s; kmp(s); int n = s.length(); if (p[n - 1] == 0) cout << "Just a legend"; else { int x = 0, ans = p[n - 1]; for (int i = 1; i < n - 1; i++) x = max(x, p[i]); while (ans != 0) { if (ans <= x) break; else ans = p[ans - 1]; } if (ans == 0) cout << "Just a legend"; else { for (int i = 0; i < ans; i++) cout << s[i]; } } return 0; }
#include <bits/stdc++.h> using namespace std; string s; int main() { cin >> s; int N = s.length(); int i = 1, j = 0; int lps[1000001]; lps[0] = 0; while (i < N) { if (s[i] == s[j]) { lps[i] = j + 1; i++, j++; } else { if (j != 0) j = lps[j - 1]; else lps[i++] = 0; } } if (lps[N - 1] == 0) { cout << "Just a legend" << endl; return 0; } else { for (int i = 1; i < N - 1; i++) { if (lps[i] == lps[N - 1]) { for (int j = 0; j < lps[i]; j++) cout << s[j]; cout << endl; return 0; } } } if (lps[lps[N - 1] - 1] == 0) { cout << "Just a legend" << endl; return 0; } else { for (int j = 0; j < lps[lps[N - 1] - 1]; j++) cout << s[j]; cout << endl; return 0; } return 0; }
#include <bits/stdc++.h> using namespace std; long long mod1 = 1e9 + 7; long long mod2 = 998244353; long long mul(long long x, long long y) { return (1ll * (x % mod1) * (y % mod1)); } long long power(long long x, long long y) { long long z = 1; while (y > 0) { if (y % 2) z = mul(z, x); x = mul(x, x); y /= 2; } return z; } long long gcd(long long a, long long b) { if (a < b) return gcd(b, a); if (b == 0) return a; return gcd(b, a % b); } long long min(long long a, long long b) { if (a < b) return a; return b; } long long max(long long a, long long b) { if (a > b) return a; return b; } long long pref[(long long)1e7]; string sol(const string& s) { string a = s; long long c = 0; for (int i = 1; i < (int)a.size(); i++) { while (c != 0 && a[c] != a[i]) c = pref[c - 1]; if (a[c] == a[i]) c++; pref[i] = c; } return s.substr(0, c); } int main() { ios::sync_with_stdio(false); cin.tie(0); string s; cin >> s; string t = sol(s); long long n = s.size(), m = t.size(); long long f = 1; if (m == 0) { cout << "Just a legend" << endl; } else { for (long long i = 1; i < n - 1; i++) { if (pref[i] == m) { f = 0; cout << t << endl; break; } } string st = s.substr(0, pref[m - 1]); if (f) { if (st.size() == 0 || m == 0) { cout << "Just a legend" << endl; } else { cout << st << endl; } } } }
#include <bits/stdc++.h> using namespace std; auto speedup = []() { std::ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr); return nullptr; }(); static const auto io_sync_off = []() { std::ios::sync_with_stdio(false); std::cin.tie(nullptr); return 0; }(); vector<int> prefixFunction(string s) { int n = s.size(); vector<int> p(n); p[0] = 0; for (int i = 1; i < n; i++) { int j = p[i - 1]; while (j > 0 && s[i] != s[j]) j = p[j - 1]; if (s[i] == s[j]) j++; p[i] = j; } return p; } bool check(string s, int len) { long long int hash = 0, mod = 1000000007, keyHash = 0; long long int pow = 1; for (int i = 0; i < len - 1; i++) { pow = (pow * 26) % mod; } for (int i = 0; i < len; i++) { keyHash = ((keyHash * 26) % mod + s[i] - 'a') % mod; } for (int i = 1; i <= len; i++) { hash = ((hash * 26) % mod + s[i] - 'a') % mod; } if (hash == keyHash) return true; for (int i = len + 1; i < s.size() - 1; i++) { hash = ((hash - (pow * (s[i - len] - 'a')) % mod) + mod) % mod; hash = ((hash * 26) % mod + s[i] - 'a') % mod; if (hash == keyHash) return true; } return false; } int main() { string s, imp = "Just a legend"; cin >> s; int n = s.size(); vector<int> p = prefixFunction(s); int len = p[n - 1]; if (len == 0) { cout << imp << endl; } else { if (len <= s.size() - 2 && check(s, len)) { cout << s.substr(0, len) << endl; } else { len = p[len - 1]; if (len <= 0) { cout << imp << endl; } else { if (check(s, len)) { cout << s.substr(0, len) << endl; } else { cout << imp << endl; } } } } }
#include <bits/stdc++.h> #pragma GCC optimize(3) using namespace std; const int maxn = 1000005; int nxt[maxn]; char a[maxn], b[maxn]; int main() { scanf("%s", a + 1); int n = strlen(a + 1); int m = n; for (register int i = 1; i <= n; i++) { b[i] = a[i]; } for (register int i = 2, j; i <= n; i++) { j = nxt[i - 1]; while (j && a[i] != a[j + 1]) { j = nxt[j]; } if (a[i] == a[j + 1]) { j++; } nxt[i] = j; } if (!nxt[n]) { printf("Just a legend"); return 0; } while (1) { n = nxt[n]; if (n == 0) { break; } for (int i = nxt[n]; i <= m - 1; i++) { if (nxt[i] == n) { for (register int k = 1; k <= n; k++) { printf("%c", b[k]); } return 0; } } } printf("Just a legend"); return 0; }
#include <bits/stdc++.h> using namespace std; const long long int INF = 1e18; const int inf = 1e9; const int MOD = 1e9 + 7; const int nax = 1000000 + 10; int fail[nax]; int main() { std::ios::sync_with_stdio(0); string s; cin >> s; int len = s.length(); fail[0] = 0; int i = 1, j = 0; while (i < len) { if (s[j] != s[i]) { if (j == 0) fail[i] = 0, i++; else j = fail[j - 1]; } else { fail[i] = j + 1; i++, j++; } } int last = fail[len - 1]; int slast = fail[last - 1]; int flag = 0; if (last == 0) flag = 1; int mainflag = 0; for (int i = 0; i < len - 1; i++) { if (fail[i] == last) mainflag = 1; } if (mainflag == 1 && flag == 0) { cout << s.substr(0, last) << endl; return 0; } if (slast == 0) flag = 1; mainflag = 1; if (mainflag == 1 && flag == 0) { cout << s.substr(0, slast) << endl; return 0; } cout << "Just a legend"; return 0; }
#include <bits/stdc++.h> using namespace std; #pragma comment(linker, "/STACK:64000000") inline void imp() { printf("Just a legend\n"); exit(0); } string s; int n; long long H[1 << 20]; long long PP[1 << 20]; inline long long getHash(int l, int r) { long long res = H[r]; if (l) res -= H[l - 1] * PP[r - l + 1]; return res; } inline int check(int l) { long long PH = getHash(0, l - 1); for (int i = 1; i + l < n; ++i) { long long curHash = getHash(i, i + l - 1); if (curHash == PH) return 1; } return 0; } int main() { cin >> s; n = (int)s.length(); if (n < 3) imp(); H[0] = (long long)s[0]; for (int i = 1; i < n; ++i) H[i] = H[i - 1] * 1103 + (long long)s[i]; PP[0] = 1; for (int i = 1; i <= n; ++i) PP[i] = PP[i - 1] * 1103; int res = -1; int l = 1, r = n - 2; while (l <= r) { int mid = (l + r) >> 1; if (check(mid)) { res = mid; l = mid + 1; } else { r = mid - 1; } } if (res == -1) imp(); for (; res; --res) { if (getHash(0, res - 1) == getHash(n - res, n - 1)) break; } if (!res) res = -1; if (res != -1) { for (int i = 0; i < res; ++i) printf("%c", s[i]); printf("\n"); return 0; } imp(); return 0; }
#include <bits/stdc++.h> using namespace std; vector<int> fail(const string &s) { int n = s.length(); vector<int> v(n + 1, 0); int tmp = 0; for (int i = 1; i < n; i++) { while (tmp && s[tmp] != s[i]) tmp = v[tmp]; if (s[tmp] == s[i]) tmp++; v[i + 1] = tmp; } return v; } void solve() { string s; cin >> s; int n = s.length(); vector<int> v = fail(s); if (v[n] == 0) cout << "Just a legend"; else { int f = 0; for (int i = 1; i < n; i++) { if (v[i] == v[n]) { f = v[i]; break; } } if (f) { for (int i = 0; i < f; i++) cout << s[i]; } else if (v[v[n]] == 0) cout << "Just a legend"; else for (int i = 0; i < v[v[n]]; i++) cout << s[i]; } } int main() { ios::sync_with_stdio(0); cin.tie(0); int t = 1; solve(); }
#include <bits/stdc++.h> using namespace std; const int MN = 1e6 + 44; const int mod = 1e9 + 9, b = 128183; long long rcshnt[MN]; int n; char a[MN]; bool check(int len) { ; long long curr = 0; for (int i = 0; i < len; ++i) curr = (curr * b + a[i]) % mod; long long pre = curr; ; for (int i = len; i < n - 1; ++i) { ; ; curr = ((curr - a[i - len] * rcshnt[len - 1]) % mod * b + a[i]) % mod; ; if ((pre - curr) % mod == 0) { ; return true; } }; return false; } int main() { scanf("%s", a); n = strlen(a); rcshnt[0] = 1; for (int i = 1; i < MN; ++i) { rcshnt[i] = rcshnt[i - 1] * b % mod; } for (int i = 0; i < 10; ++i) ; vector<int> pre; long long ph = 0, sh = 0; for (int i = 0; i < n - 1; ++i) { ph = (ph * b + a[i]) % mod; sh = (sh + a[n - i - 1] * rcshnt[i]) % mod; if (ph == sh) { pre.push_back(i + 1); ; } } int low = 1, high = n - 1, ans = 0; while (low <= high) { int med = (low + high) / 2; if (check(med)) { ans = med; low = med + 1; } else high = med - 1; } int res = -1; for (auto c : pre) { if (c <= ans) res = max(res, c); } if (res <= 0) { printf("Just a legend\n"); } else { a[res] = 0; printf("%s\n", a); } }
#include <bits/stdc++.h> using namespace std; const long long linf = 1e18 + 5; const int mod = (int)1e9 + 7; const int inf = 1e9; long long read() { bool minus = false; long long result = 0; char ch; ch = getchar(); while (true) { if (ch == '-') break; if (ch >= '0' && ch <= '9') break; ch = getchar(); } if (ch == '-') minus = true; else result = ch - '0'; while (true) { ch = getchar(); if (ch < '0' || ch > '9') break; result = result * 10 + (ch - '0'); } if (minus) { return -result; } else { return result; } } long long fpow(long long base, long long power) { long long result = 1; while (power > 0) { if (power % 2 == 1) result = (result * base); base = (base * base); power /= 2; } return result; } long long lps[1000100]; vector<long long> v[1000100]; inline void Prefix(string str) { long long i, j, n = str.size(); i = 0, j = 1; lps[0] = 0; while (i < n && j < n) { if (str[i] == str[j]) { lps[j] = i + 1; j++; i++; } else { if (i > 0) { i = lps[i - 1]; } else { lps[j] = 0; j++; } } if (j == n) break; } } inline void Sukeesh(long long n) { for (long long i = 0; i < n; i++) { v[lps[i]].push_back(i); } } bool check(long long n, long long no) { for (long long i = 0; i < v[n].size(); i++) { if (v[n][i] != no) return 1; } return 0; } int main() { string str; cin >> str; Prefix(str); Sukeesh(str.size()); long long n = str.size() - 1; while (n > 0) { if (lps[n] > 0) { if (check(lps[n], str.size() - 1)) { for (long long i = 0; i < lps[n]; i++) { cout << str[i]; } return 0; } } else { return 0 * printf("Just a legend"); } n = lps[n] - 1; } return 0 * printf("Just a legend"); }
#include <bits/stdc++.h> using namespace std; class node { public: long long int second; long long int length; }; int main() { string pattern; cin >> pattern; long long int i, m, n, j; n = pattern.length(); long long int dfa[n]; memset(dfa, 0, sizeof(dfa)); long long int x = 0; for (i = 1; i < n; i++) { if (pattern[i] == pattern[x]) x++, dfa[i] = x; else if (x > 0) { x = dfa[x - 1]; i--; } } for (i = 0; i < n - 1; i++) if (dfa[n - 1] > 0 && dfa[i] == dfa[n - 1]) { for (j = 0; j < dfa[n - 1]; j++) printf("%c", pattern[j]); cout << endl; break; } if (i == n - 1 && dfa[n - 1] > 0 && dfa[dfa[n - 1] - 1] > 0) { for (j = 0; j < dfa[dfa[n - 1] - 1]; j++) printf("%c", pattern[j]); cout << endl; } else if (i == n - 1) cout << "Just a legend\n"; return 0; }
#include <bits/stdc++.h> using namespace std; void func() { string s; cin >> s; long long n = s.length(); long long i = 1, len = 0, pre[n]; pre[0] = 0; while (i < n) { if (s[i] == s[len]) { len++; pre[i++] = len; } else { if (len == 0) { pre[i++] = 0; } else { len = pre[len - 1]; } } } if (pre[n - 1] == 0) { cout << "Just a legend" << "\n"; return; } for (long long i = 0; i < n - 1; ++i) { if (pre[i] == pre[n - 1]) { cout << s.substr(0, pre[n - 1]) << "\n"; return; } } if (pre[pre[n - 1] - 1] == 0) { cout << "Just a legend" << "\n"; return; } cout << s.substr(0, pre[pre[n - 1] - 1]) << "\n"; } int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); long long t = 1; while (t--) { func(); } }
#include <bits/stdc++.h> using namespace std; const int P = 2017, M = 1e9 + 7; string s; int n; vector<int> p, h; int get(int l, int r) { if (!l) return h[r]; return h[r] - h[l - 1] * p[r - l + 1]; } int bs(int i) { int l = 0, r = n - i; while (l != r - 1) { int m = (l + r) / 2; if (get(i, i + m - 1) == get(0, m - 1)) { l = m; } else { r = m; } } return l; } int main() { cin >> s; n = s.size(); if (s.size() < 3) { cout << "Just a legend"; return 0; } if (s[0] == s[1] && s[1] == s[2] && s.size() == 3) { cout << s[0]; return 0; } else if (s.size() == 3) { cout << "Just a legend"; return 0; } p.resize(n); h.resize(n); p[0] = 1; for (int i = 1; i < n; i++) { p[i] = p[i - 1] * P; } h[0] = s[0] - 'a' + 1; for (int i = 1; i < n; i++) { h[i] = h[i - 1] * P + s[i] - 'a' + 1; } int ans = 0; for (int i = 1; i < n - 1; i++) { ans = max(ans, bs(i)); } set<int> st; for (int i = 0; i < n; i++) { if (get(i, n - 1) == get(0, n - i - 1)) { st.insert(n - i); } } if (ans == 0 || st.upper_bound(ans) == st.begin()) { cout << "Just a legend"; return 0; } cout << s.substr(0, *(--st.upper_bound(ans))); }
#include <bits/stdc++.h> using namespace std; char a[1000005]; int ne[1000005], n, maxx = 0; void c() { ne[1] = 0; for (int i = 2, j = 0; i <= n; i++) { while (j && a[i] != a[j + 1]) { j = ne[j]; } if (a[i] == a[j + 1]) { j++; } ne[i] = j; if (i != n) { maxx = max(ne[i], maxx); } } } int main() { cin >> a + 1; n = strlen(a + 1); c(); int x = ne[n]; if (x == 0) { printf("Just a legend\n"); } else { while (x > maxx) { x = ne[x]; } if (x == 0) { printf("Just a legend\n"); return 0; } for (int i = 2; i < n; i++) if (x == ne[i]) { for (int j = i - ne[i] + 1; j <= i; j++) { printf("%c", a[j]); } printf("\n"); return 0; } } return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = 1e9 + 9; const long long LINF = 1e12; const int MAXN = 1e6 + 5; const int MOD = 1e9 + 7; const double eps = 1e-14; int n; int pf[MAXN]; string s; void pref_func() { for (int i = 1; i < n; i++) { int j = pf[i - 1]; while (j > 0 && s[i] != s[j]) j = pf[j - 1]; if (s[i] == s[j]) j++; pf[i] = j; } } void solve() { cin >> s; n = s.size(); pref_func(); int k = 0; for (int i = 1; i < n - 1; i++) { if (pf[i] == pf[n - 1]) k = pf[n - 1]; } for (int i = 1; i < n - 1; i++) { if (pf[i] == pf[pf[n - 1] - 1]) k = max(k, pf[pf[n - 1] - 1]); } if (k) { for (int i = 0; i < k; i++) cout << s[i]; } else cout << "Just a legend"; } int main() { if (!1) { freopen( "474" ".in", "r", stdin); freopen( "474" ".out", "w", stdout); } ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); int t = 1; while (t--) solve(); return 0; }
#include <bits/stdc++.h> using namespace std; const int MAXN = 1e6; const long long z = 131, MOD = 1e9 + 21; long long Z[MAXN + 1]; void fillZ() { Z[0] = 1; for (int n = 1; n <= MAXN; ++n) Z[n] = z * Z[n - 1] % MOD; } struct RollingHashing { vector<long long> H; RollingHashing(string &S) { int N = S.length(); H.resize(N + 1); H[N] = 0; for (int i = N - 1; i >= 0; --i) H[i] = (S[i] + z * H[i + 1]) % MOD; } long long hash(int i, int k) { long long ans = (H[i] - Z[k] * H[i + k]) % MOD; return ans >= 0 ? ans : ans + MOD; } }; int main() { fillZ(); string s; cin >> s; int lens = s.length(); int lent = lens - 2; RollingHashing rs(s); long long prefix, suffix, mid; int i; while (lent > 0) { prefix = rs.hash(0, lent); suffix = rs.hash(lens - lent, lent); if (prefix == suffix) { i = 1; while (i + lent < lens) { mid = rs.hash(i, lent); if (mid == prefix) { for (int j = 0; j < lent; ++j) { cout << s[j]; } cout << '\n'; return 0; } ++i; } } --lent; } cout << "Just a legend\n"; return 0; }
#include <bits/stdc++.h> using namespace std; const int MN = 1e6 + 44; const int mod = 1e9 + 9, b = 8888; long long rcshnt[MN]; int n; char a[MN]; bool check(int len) { ; long long curr = 0; for (int i = 0; i < len; ++i) curr = (curr * b + a[i]) % mod; long long pre = curr; ; for (int i = len; i < n - 1; ++i) { ; ; curr = ((curr - a[i - len] * rcshnt[len - 1]) % mod * b + a[i]) % mod; ; if ((pre - curr) % mod == 0) { ; return true; } }; return false; } int main() { scanf("%s", a); n = strlen(a); rcshnt[0] = 1; for (int i = 1; i < MN; ++i) { rcshnt[i] = rcshnt[i - 1] * b % mod; } for (int i = 0; i < 10; ++i) ; vector<int> pre; long long ph = 0, sh = 0; for (int i = 0; i < n - 1; ++i) { ph = (ph * b + a[i]) % mod; sh = (sh + a[n - i - 1] * rcshnt[i]) % mod; if (ph == sh) { pre.push_back(i + 1); ; } } int low = 1, high = n - 1, ans = 0; while (low <= high) { int med = (low + high) / 2; if (check(med)) { ans = med; low = med + 1; } else high = med - 1; } int res = -1; for (auto c : pre) { if (c <= ans) res = max(res, c); } if (res <= 0) { printf("Just a legend\n"); } else { a[res] = 0; printf("%s\n", a); } }
#include <bits/stdc++.h> using namespace std; const int Alp = 26; const int __PRECISION = 9; const int inf = 1e9 + 8; const long double PI = acos(-1); const long double EPS = 1e-7; const long long MOD = 1e9 + 7; const long long MAXN = 2e5 + 5; const long long ROOTN = 320; const long long LOGN = 18; const long long INF = 1e18 + 1022; vector<int> z_function(string s) { int n = (int)s.length(); vector<int> z(n); for (int i = 1, l = 0, r = 0; i < n; ++i) { if (i <= r) z[i] = min(r - i + 1, z[i - l]); while (i + z[i] < n && s[z[i]] == s[i + z[i]]) ++z[i]; if (i + z[i] - 1 > r) l = i, r = i + z[i] - 1; } return z; } signed main() { ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); string S; cin >> S; vector<int> zz = z_function(S); int mx = 0; for (int i = 1; i <= ((int)S.size() - 1); ++i) { if (zz[i] == (int)S.size() - i && zz[i] <= mx) { cout << S.substr(i) << '\n'; exit(0); } mx = max(mx, zz[i]); } cout << "Just a legend\n"; return 0; }