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#include <bits/stdc++.h> using namespace std; int n, k; vector<int> v[1000007]; int lvl[1000007]; int cnt[1000007]; int mndepth[1000007]; int noreturn[1000007]; void init(int vertex) { int sz = v[vertex].size(); if (sz == 0) { cnt[vertex] = 1; mndepth[vertex] = lvl[vertex]; return; } mndepth[vertex] = 1000007; for (int i = 0; i < sz; ++i) { int h = v[vertex][i]; lvl[h] = lvl[vertex] + 1; init(h); if (mndepth[h] <= lvl[vertex] + k) { cnt[vertex] += cnt[h]; mndepth[vertex] = min(mndepth[vertex], mndepth[h]); } } } void dfs(int vertex) { int sz = v[vertex].size(); if (sz == 0) { noreturn[vertex] = 1; return; } for (int i = 0; i < sz; ++i) { dfs(v[vertex][i]); } for (int i = 0; i < sz; ++i) { int h = v[vertex][i]; int aux = cnt[vertex]; if (mndepth[h] <= lvl[vertex] + k) { aux -= cnt[h]; } noreturn[vertex] = max(noreturn[vertex], aux + noreturn[h]); } } void input() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; ++i) { int x; scanf("%d", &x); v[x].push_back(i); } } void solve() { init(1); dfs(1); printf("%d\n", noreturn[1]); } int main() { ios_base ::sync_with_stdio(false); cin.tie(NULL); input(); solve(); return 0; }
#include <bits/stdc++.h> using namespace std; const long double pi = acos(-1.0); const long double log23 = 1.58496250072115618145373894394781; const long double eps = 1e-8; const long long INF = 1e18 + 239; const long long prost = 239; const int two = 2; const int th = 3; const long long MOD = 998244353; const long long MOD2 = MOD * MOD; const int BIG = 1e9 + 239; const int alf = 26; const int dx[4] = {-1, 0, 1, 0}; const int dy[4] = {0, 1, 0, -1}; const int dxo[8] = {-1, -1, -1, 0, 1, 1, 1, 0}; const int dyo[8] = {-1, 0, 1, 1, 1, 0, -1, -1}; const int dig = 10; const int day[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; const int digarr[10] = {6, 2, 5, 5, 4, 5, 6, 3, 7, 6}; const int bt = 31; template <typename T> inline T gcd(T a, T b) { while (a) { b %= a; swap(a, b); } return b; } template <typename T> inline T lcm(T a, T b) { return (a / gcd(a, b)) * b; } inline bool is_down(char x) { return ('a' <= x && x <= 'z'); } inline bool is_upper(char x) { return ('A' <= x && x <= 'Z'); } inline bool is_digit(char x) { return ('0' <= x && x <= '9'); } mt19937 rnd(239); const int M = 1e6 + 239; const int N = 2 * 1e3 + 239; const int L = 20; const int T = (1 << 18); const int B = trunc(sqrt(M)) + 1; const int X = 150; int n, k, r, comp[M], dp[M]; vector<int> d[M]; bool used[M]; vector<int> v[M], u[M], in[M]; vector<int> tp; void dfs_go(int p) { used[p] = true; for (int i : v[p]) if (!used[i]) dfs_go(i); tp.push_back(p); } void dfs_back(int p) { in[r].push_back(p); if (d[p].empty()) dp[r]++; used[p] = true; comp[p] = r; for (int i : u[p]) if (!used[i]) dfs_back(i); } int st[M]; void dfs_tree(int p, int h) { st[h] = p; for (int i : d[p]) dfs_tree(i, h + 1); if (d[p].empty()) { if (h < k) v[p].push_back(0); else v[p].push_back(st[h - k]); } } int main() { ios::sync_with_stdio(0); cin >> n >> k; for (int i = 1; i < n; i++) { int p; cin >> p; d[p - 1].push_back(i); v[p - 1].push_back(i); } dfs_tree(0, 0); for (int i = 0; i < n; i++) if (!used[i]) dfs_go(i); for (int i = 0; i < n; i++) for (int j : v[i]) u[j].push_back(i); reverse(tp.begin(), tp.end()); memset(used, 0, sizeof(used)); r = 0; for (int i = 0; i < n; i++) { int x = tp[i]; if (!used[x]) { dfs_back(x); r++; } } for (int i = r - 1; i >= 0; i--) { int pl = 0; for (int x : in[i]) for (int it : v[x]) { if (comp[it] == i) continue; pl = max(pl, dp[comp[it]]); } dp[i] += pl; } cout << dp[comp[0]]; return 0; }
#include <bits/stdc++.h> using namespace std; template <class T> inline bool cmin(T& a, const T& b) { return a > b ? a = b, 1 : 0; } template <class T> inline bool cmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; } const int N = 1e6 + 5; const int INF = 0x3f3f3f3f; int head[N], nxt[N], ver[N], tot; void add(int u, int v) { ver[++tot] = v, nxt[tot] = head[u], head[u] = tot; } int dp[N], a[N], h[N], n, k; void dfs(int u) { h[u] = INF; for (int i = head[u]; i; i = nxt[i]) { int v = ver[i]; dfs(v); cmin(h[u], h[v] + 1); a[u] += a[v]; cmax(dp[u], dp[v] - a[v]); } dp[u] += a[u]; if (h[u] == INF) dp[u] = a[u] = 1, h[u] = 0; if (h[u] >= k) a[u] = 0; } int main() { cin >> n >> k; for (int i = 2; i <= n; i++) { int fa; cin >> fa; add(fa, i); } dfs(1); cout << dp[1] << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int gcd(int a, int b) { return b == 0 ? a : gcd(b, a % b); } const int MAXN = 1000000; int n, lim; int par[MAXN]; vector<int> ch[MAXN]; int dleaf[MAXN]; int dp[MAXN]; void dfsinit(int at) { dleaf[at] = ((int)(ch[at]).size()) == 0 ? 0 : INT_MAX; dp[at] = ((int)(ch[at]).size()) == 0 ? 1 : 0; for (int i = (0); i < (((int)(ch[at]).size())); ++i) { int to = ch[at][i]; dfsinit(to); dleaf[at] = min(dleaf[at], 1 + dleaf[to]); if (dleaf[to] <= lim - 1) dp[at] += dp[to]; } } int dfsans(int at) { int ret = dp[at]; for (int i = (0); i < (((int)(ch[at]).size())); ++i) { int to = ch[at][i]; int cur = dp[at] + dfsans(to) - (dleaf[to] <= lim - 1 ? dp[to] : 0); ret = max(ret, cur); } return ret; } int solve() { for (int i = (0); i < (n); ++i) if (par[i] != -1) ch[par[i]].push_back(i); dfsinit(0); return dfsans(0); } void run() { scanf("%d%d", &n, &lim); par[0] = -1; for (int i = (1); i < (n); ++i) scanf("%d", &par[i]), --par[i]; printf("%d\n", solve()); } int main() { run(); return 0; }
#include <bits/stdc++.h> using namespace std; vector<vector<long long> > adj; vector<long long> util[2]; vector<long long> ht; vector<long long> res; long long n, k; void dfs(long long r) { if (adj[r].size() == 0) { util[0][r] = ht[r] - k; util[1][r] = 1; return; } for (long long i = 0; i < adj[r].size(); i++) { long long c = adj[r][i]; ht[c] = ht[r] + 1; dfs(c); if (util[0][c] <= ht[r]) { util[0][r] = min(util[0][r], util[0][c]); util[1][r] += util[1][c]; } } } void solve(long long r) { res[r] = 1; for (long long i = 0; i < adj[r].size(); i++) { long long c = adj[r][i]; solve(c); if (util[0][c] <= ht[r]) { res[r] = max(res[r], (util[1][r] - util[1][c]) + res[c]); } else res[r] = max(res[r], util[1][r] + res[c]); } } int main() { ios_base::sync_with_stdio(false); cin >> n >> k; adj.clear(); adj.resize(n); ht.clear(); ht.resize(n, 0); res.clear(); res.resize(n, 0); util[0].resize(n, n + 5); util[1].resize(n, 0); for (long long i = 1; i < n; i++) { long long p; cin >> p; p--; adj[p].push_back(i); } dfs(0); solve(0); cout << res[0] << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int n, k; vector<int> edge[1000000 + 10]; int deep[1000000 + 10], dp[1000000 + 10], low[1000000 + 10]; int ans[1000000 + 10]; void dfs(int rt, int first) { deep[rt] = deep[first] + 1; if (edge[rt].size() == 1 && rt != 1) { low[rt] = deep[rt]; dp[rt] = 1; return; } int minn = 1e9; for (auto i : edge[rt]) { if (i == first) continue; dfs(i, rt); if (deep[rt] + k >= low[i]) { minn = min(minn, low[i]); dp[rt] += dp[i]; } } low[rt] = minn; } void dfs1(int rt, int first) { ans[rt] = dp[rt]; for (auto i : edge[rt]) { if (i == first) continue; int tmp = dp[i]; if (deep[rt] + k >= low[i]) { dfs1(i, rt); ans[rt] = max(ans[rt], dp[rt] - tmp + ans[i]); } else { dfs1(i, rt); ans[rt] = max(ans[rt], dp[rt] + ans[i]); } } } int main() { ios::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin >> n >> k; for (int i = (2); i < (n + 1); i++) { int x; cin >> x; edge[i].push_back(x); edge[x].push_back(i); } dfs(1, 0); dfs1(1, 0); cout << ans[1] << "\n"; return 0; }
#include <bits/stdc++.h> using namespace std; const long long nr = 1e6 + 500; inline long long read() { long long ret = 0; long long x = 1; char ch = getchar(); while (!isdigit(ch)) { if (ch == '-') x = -1; ch = getchar(); } while (isdigit(ch)) { ret = ret * 10 + ch - '0'; ch = getchar(); } return ret * x; } long long fir[nr]; long long item = 0; struct edge { long long nxt, to, val; } p[nr * 2]; void add(long long a, long long b, long long c) { ++item; p[item].val = c; p[item].to = b; p[item].nxt = fir[a]; fir[a] = item; } long long leave[nr]; long long low[nr]; bool islve[nr]; long long n, k; long long depth[nr]; void dfs1(long long now, long long fat) { depth[now] = depth[fat] + 1; if (islve[now]) { low[now] = depth[now]; } for (int tmp = fir[now]; tmp; tmp = p[tmp].nxt) { long long v = p[tmp].to; if (v == fat) continue; dfs1(v, now); low[now] = min(low[now], low[v]); } } void dfs2(long long now, long long fat) { if (islve[now]) { leave[now] = 1; } for (int tmp = fir[now]; tmp; tmp = p[tmp].nxt) { long long v = p[tmp].to; if (v == fat) continue; dfs2(v, now); if (low[v] - depth[now] <= k) { leave[now] += leave[v]; leave[v] = 0; } } } long long dfsans(long long now) { long long maxx = 0; for (int tmp = fir[now]; tmp; tmp = p[tmp].nxt) { long long v = p[tmp].to; maxx = max(maxx, dfsans(v)); } return maxx + leave[now]; } int main() { n = read(); k = read(); memset(low, 999999, sizeof(low)); memset(islve, 1, sizeof(islve)); for (int i = 2; i <= n; i++) { long long f = read(); add(f, i, 1); islve[f] = 0; } dfs1(1, 0); dfs2(1, 0); cout << dfsans(1); return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 1e6 + 100; vector<int> e[maxn]; int n, k; int low[maxn], dp1[maxn], dp2[maxn], h[maxn]; void dfs(int u) { if (e[u].size() == 0) low[u] = h[u], dp1[u] = 1; else low[u] = n; for (auto &v : e[u]) { h[v] = h[u] + 1; dfs(v); if (low[v] - h[u] <= k) { dp1[u] += dp1[v]; low[u] = min(low[u], low[v]); dp2[u] = max(dp2[u], dp2[v] - dp1[v]); } else dp2[u] = max(dp2[u], dp2[v]); } dp2[u] += dp1[u]; return; } int main() { ios_base::sync_with_stdio(0); cin >> n >> k; for (int i = 2; i <= n; i++) { int v; cin >> v; e[v].push_back(i); } dfs(1); cout << dp2[1]; return 0; }
#include <bits/stdc++.h> using namespace std; const int MAXN = 1000100; int N, K; vector<int> child[MAXN]; int nfree[MAXN], npaid[MAXN], dep[MAXN]; void flood(int cloc) { if (!child[cloc].size()) { dep[cloc] = 0; nfree[cloc] = 1; npaid[cloc] = 0; return; } int pbest = 0, ftot = 0; dep[cloc] = 1e9; for (int son : child[cloc]) { flood(son); dep[cloc] = min(dep[cloc], dep[son] + 1); ftot += nfree[son]; pbest = max(pbest, npaid[son]); } npaid[cloc] = pbest; if (dep[cloc] < K) nfree[cloc] += ftot; else npaid[cloc] += ftot; } int main() { ios_base::sync_with_stdio(0); cin.tie(NULL); cin >> N >> K; for (int i = 1; i < N; i++) { int a; cin >> a; a--; child[a].push_back(i); } flood(0); cout << nfree[0] + npaid[0] << "\n"; }
#include <bits/stdc++.h> const int maxn = 1e6 + 5; const int maxm = 2e6 + 5; using namespace std; int n, k; int tot, head[maxn]; int a[maxn], b[maxn]; int ans; struct edgenode { int to, next; } edge[maxm]; void addedge(int u, int v) { edge[tot].to = v; edge[tot].next = head[u]; head[u] = tot++; } void dfs1(int x) { if (head[x] == -1) { a[x] = 1; b[x] = k; return; } for (int i = head[x]; i != -1; i = edge[i].next) { int v = edge[i].to; dfs1(v); if (b[v]) a[x] += a[v]; b[x] = max(b[x], b[v] - 1); } } void dfs2(int x, int val) { if (head[x] == -1) { ans = max(ans, val + 1); return; } for (int i = head[x]; i != -1; i = edge[i].next) { int v = edge[i].to; if (b[v]) dfs2(v, val + a[x] - a[v]); else dfs2(v, val + a[x]); } } int main() { memset(head, -1, sizeof head); scanf("%d%d", &n, &k); for (int i = 2; i <= n; i++) { int x; scanf("%d", &x); addedge(x, i); } dfs1(1); dfs2(1, 0); printf("%d\n", ans); return 0; }
#include <bits/stdc++.h> using namespace std; int n, k; struct graph { int head[1000005], nxt[1000005], to[1000005], ecnt; graph() { ecnt = 0; memset(head, 0, sizeof(head)); memset(nxt, 0, sizeof(nxt)); memset(to, 0, sizeof(to)); } void adde(int u, int v) { to[++ecnt] = v; nxt[ecnt] = head[u]; head[u] = ecnt; } } t; int dep[1000005], deg[1000005], dp[1000005], mn[1000005]; void dfs(int x) { if (deg[x] == 0) { mn[x] = dep[x]; dp[x] = 1; return; } mn[x] = 0x3f3f3f3f; for (int e = t.head[x]; e; e = t.nxt[e]) { int y = t.to[e]; dep[y] = dep[x] + 1; dfs(y); mn[x] = min(mn[x], mn[y]); if (mn[y] - dep[x] <= k) { dp[x] += dp[y]; dp[y] = 0; } } } int mxsum(int x) { int mx = 0; for (int e = t.head[x]; e; e = t.nxt[e]) { mx = max(mx, mxsum(t.to[e])); } return mx + dp[x]; } int main() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; i++) { int fa; scanf("%d", &fa); t.adde(fa, i); deg[fa]++; } dfs(1); printf("%d\n", mxsum(1)); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000010; int depth[N]; vector<int> g[N]; int k, n; int minleaf[N]; bool leaf(int u) { return u != 1 and g[u].size() == 0; } void dfs(int u, int d) { depth[u] = d; if (leaf(u)) minleaf[u] = d; else minleaf[u] = 0x3f3f3f3f; for (int v : g[u]) { dfs(v, d + 1); minleaf[u] = min(minleaf[u], minleaf[v]); } } int cnt[N]; void dfs2(int u) { if (leaf(u)) { cnt[u] = 1; return; } for (int v : g[u]) dfs2(v); if (minleaf[u] - depth[u] >= k) return; for (int v : g[u]) cnt[u] += cnt[v]; } int solve(int u) { if (leaf(u)) return 1; int sum = 0; for (int v : g[u]) sum += cnt[v]; int ans = 0; for (int v : g[u]) ans = max(ans, sum - cnt[v] + solve(v)); return ans; } int main() { scanf("%d %d", &n, &k); for (int i = 2; i <= n; i++) { int p; scanf("%d", &p); g[p].push_back(i); } dfs(1, 0); dfs2(1); printf("%d\n", solve(1)); return 0; }
#include <bits/stdc++.h> using namespace std; template <typename Arg1> void __f(const char* name, Arg1&& arg1) { cerr << name << " : " << arg1 << std::endl; } template <typename Arg1, typename... Args> void __f(const char* names, Arg1&& arg1, Args&&... args) { const char* comma = strchr(names + 1, ','); cerr.write(names, comma - names) << " : " << arg1 << " | "; __f(comma + 1, args...); } template <class T> ostream& operator<<(ostream& os, vector<T> V) { os << "[ "; for (auto v : V) os << v << " "; return os << "]"; } template <class L, class R> ostream& operator<<(ostream& os, pair<L, R> P) { return os << "(" << P.first << "," << P.second << ")"; } template <typename T, typename U> pair<T, U> operator+(const pair<T, U>& l, const std::pair<T, U>& r) { return {l.first + r.first, l.second + r.second}; } const long long int mod = 1e9 + 7; const int maxn = 1000005; vector<long long int> g[maxn]; long long int dp[maxn]; long long int n, k; pair<long long int, long long int> dfs(long long int u, long long int d = 0) { pair<long long int, long long int> now = {1e9, 0}; dp[u] = -1e9; for (auto v : g[u]) { pair<long long int, long long int> temp = dfs(v, d + 1); if (temp.first <= d) { now.first = min(now.first, temp.first); now.second += temp.second; dp[u] = max(dp[u], dp[v] - temp.second); } else { dp[u] = max(dp[u], dp[v]); } } if (g[u].size() == 0) { now = {d - k, 1}; dp[u] = 1; } else { dp[u] += now.second; } return now; } int32_t main() { ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); cin >> n >> k; for (long long int i = 1; i <= n - 1; i++) { long long int p; cin >> p; g[p].push_back(i + 1); } dfs(1); cout << dp[1] << '\n'; }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 7; int n, k; vector<int> kid[N]; int h[N]; int lst[N]; int cm[N]; void dfs(int v) { if (!kid[v].size()) { lst[v] = h[v]; return; } lst[v] = 1e9; for (auto u : kid[v]) { h[u] = h[v] + 1; dfs(u); lst[v] = min(lst[v], lst[u]); } } void getcm(int v) { if (!kid[v].size()) { cm[v] = 1; return; } for (auto u : kid[v]) { getcm(u); if (lst[u] - h[v] <= k) cm[v] += cm[u]; } } int dp[N]; void solve(int v) { if (!kid[v].size()) { dp[v] = 1; return; } for (auto u : kid[v]) solve(u); int s = 0; for (auto u : kid[v]) if (lst[u] - h[v] <= k) s += cm[u]; for (auto u : kid[v]) if (lst[u] - h[v] <= k) dp[v] = max(dp[v], s - cm[u] + dp[u]); else dp[v] = max(dp[v], s + dp[u]); } int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n >> k; for (int i = 2; i <= n; i++) { int p; cin >> p; kid[p].push_back(i); } dfs(1); getcm(1); solve(1); cout << dp[1]; }
#include <bits/stdc++.h> using namespace std; const int N = 1000050, INF = (int)1e9; const int LOG_N = 20; int root = 0; int n, m, a, b; int val[N]; vector<int> G[N]; int dp[2][N]; int up[N], down[N]; void get(int v) { dp[0][v] = val[v]; for (int nxt : G[v]) { get(nxt); dp[0][v] += dp[0][nxt]; dp[1][v] = max(dp[1][v], dp[1][nxt]); } if (up[v] == -1) { dp[1][v] = dp[1][v] + dp[0][v]; dp[0][v] = 0; } } int dfs_val(int v, int p) { if (G[v].size() == 0) { down[v] = 0; val[v] = 1; } else { down[v] = INF; for (int nxt : G[v]) { if (nxt != p) { down[v] = min(down[v], dfs_val(nxt, v) + 1); } } } up[v] = (down[v] < m ? 1 : -1); return down[v]; } int main() { scanf("%d%d", &n, &m); for (int i = 1; i < n; i++) { int x; scanf("%d", &x); x--; G[x].push_back(i); } dfs_val(0, -1); get(0); cout << dp[0][0] + dp[1][0] << endl; }
#include <bits/stdc++.h> using namespace std; long long MOD = 1000000007; vector<vector<long long> > g; long long INF = (long long)1e9; long long N, K; long long res = 1; vector<long long> path; vector<long long> dp1; vector<long long> dp2; long long dfs(long long a) { path.push_back(a); long long ans = 0; long long mx = 0; long long base = 0; for (long long i = 0; i < g[a].size(); i++) { long long t = dfs(g[a][i]); base += dp2[g[a][i]]; dp2[a] += dp2[g[a][i]]; mx = max(mx, t - dp2[g[a][i]]); } for (long long i = 0; i < g[a].size(); i++) { dp1[a] += dp1[g[a][i]]; } if (dp1[a] == 0) { dp2[a] = 0; } ans = base + mx; if ((long long)g[a].size() == 0) { ans = 1; long long t = (long long)path.size() - K - 1; if (t >= 0) { dp1[path[t]]--; } dp1[a]++; dp2[a] = 1; } path.pop_back(); return ans; } signed main() { cin.tie(0); ios::sync_with_stdio(false); cin >> N >> K; g.resize(N); dp1.resize(N, 0); dp2.resize(N, 0); long long a; for (long long i = 0; i < N - 1; i++) { cin >> a; a--; g[a].push_back(i + 1); } cout << dfs(0) << endl; }
#include <bits/stdc++.h> using namespace std; int n, k; vector<int> child[1000001]; int par[1000001][20]; int dep[1000001]; int up[1000001]; int mnc[1000001]; void dfs(int x) { mnc[x] = 9 * n; if (child[x].empty()) mnc[x] = dep[x]; for (int i : child[x]) { par[i][0] = x; dep[i] = dep[x] + 1; dfs(i); mnc[x] = min(mnc[x], mnc[i]); } } int getPar(int x, int t) { t = max(t, 0); for (int i = 20; i--;) { if ((t >> i) & 1) x = par[x][i]; } return x; } void dfs2(int x) { if (child[x].empty()) { up[x] = 1; } else { up[x] = (mnc[x] - k < dep[x]); } for (int i : child[x]) { dfs2(i); } } int dp1[1000001]; int dp2[1000001]; void dfs3(int x) { if (child[x].empty()) { dp1[x] = 1; dp2[x] = 1; } else { int sum = 0, mx = 0; for (int i : child[x]) { dfs3(i); sum += dp1[i]; mx = max(mx, dp2[i] - dp1[i]); } dp1[x] = up[x] ? sum : 0; dp2[x] = sum + mx; } } int main() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; ++i) { int p; scanf("%d", &p); child[p].push_back(i); } dfs(1); for (int i = 1; i < 20; ++i) { for (int j = 1; j <= n; ++j) { par[j][i] = par[par[j][i - 1]][i - 1]; } } dfs2(1); dfs3(1); printf("%d\n", dp2[1]); return 0; }
#include <bits/stdc++.h> using namespace std; int n, k; int p[1000005]; int dp[1000005]; int cnt[1000005]; int ans[1000005]; vector<int> v[1000005]; void dfs0(int x) { ans[x] = dp[x]; int tmp = 0; for (auto y : v[x]) { dfs0(y); tmp = max(tmp, ans[y]); } ans[x] += tmp; } void dfs(int x) { if (v[x].empty()) { dp[x] = 1; cnt[x] = k; return; } int ma = 0; for (auto y : v[x]) { dfs(y); ma = max(ma, cnt[y]); if (cnt[y] >= 1) { dp[x] += dp[y]; dp[y] = 0; } } cnt[x] = max(0, ma - 1); } int main() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; i++) { scanf("%d", &p[i]); v[p[i]].push_back(i); } dfs(1); dfs0(1); cout << ans[1] << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000005; int dp[N][2], d[N], n, k; vector<int> adj[N]; int res; void dfs(int u) { if (adj[u].empty()) { dp[u][0] = dp[u][1] = 1; return; } d[u] = n + 1; int mx = 0; for (int v : adj[u]) { dfs(v); d[u] = min(d[u], d[v] + 1); if (d[v] < k) { dp[u][0] += dp[v][0]; dp[u][1] += dp[v][0]; mx = max(mx, dp[v][1] - dp[v][0]); } else mx = max(mx, dp[v][1]); } dp[u][1] += mx; } int main() { cin.tie(0)->sync_with_stdio(0); cin >> n >> k; for (int i = 2; i <= n; i++) { int p; cin >> p; adj[p].push_back(i); } dfs(1); cout << dp[1][1] << '\n'; }
#include <bits/stdc++.h> using namespace std; int n, k; vector<int> child[1000001]; int dep[1000001]; int mnc[1000001]; void dfs(int x) { mnc[x] = 9 * n; if (child[x].empty()) mnc[x] = dep[x]; for (int i : child[x]) { dep[i] = dep[x] + 1; dfs(i); mnc[x] = min(mnc[x], mnc[i]); } } int dp1[1000001]; int dp2[1000001]; void dfs2(int x) { if (child[x].empty()) { dp1[x] = 1; dp2[x] = 1; } else { int sum = 0, mx = 0; for (int i : child[x]) { dfs2(i); sum += dp1[i]; mx = max(mx, dp2[i] - dp1[i]); } dp1[x] = mnc[x] - k < dep[x] ? sum : 0; dp2[x] = sum + mx; } } int main() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; ++i) { int p; scanf("%d", &p); child[p].push_back(i); } dfs(1); dfs2(1); printf("%d\n", dp2[1]); return 0; }
#include <bits/stdc++.h> const int MAXN = 1000010; struct graph { int head[MAXN], nxt[MAXN << 1], to[MAXN << 1], tot; void adde(int b, int e) { nxt[++tot] = head[b]; to[head[b] = tot] = e; } } g1, g2, g3; int *head, *nxt, *to; void setg(graph* x) { head = x->head, nxt = x->nxt, to = x->to; } int n, K; int st[MAXN], top; bool isl[MAXN]; void dfs(int u, int f = 0) { st[++top] = u; bool& hav = isl[u] = true; for (int i = head[u]; i; i = nxt[i]) if (to[i] != f) { hav = false; dfs(to[i], u); g2.adde(u, to[i]); } if (hav) g2.adde(u, st[std::max(top - K, 1)]); --top; } bool ins[MAXN]; int dfn[MAXN], low[MAXN], t0t; int val[MAXN], bel[MAXN], idx; void tarjan(int u) { dfn[u] = low[u] = ++t0t; ins[st[++top] = u] = true; for (int i = head[u]; i; i = nxt[i]) if (!dfn[to[i]]) { tarjan(to[i]); low[u] = std::min(low[u], low[to[i]]); } else if (ins[to[i]]) low[u] = std::min(low[u], dfn[to[i]]); if (low[u] == dfn[u]) { int v; ++idx; do ins[v = st[top--]] = false, val[bel[v] = idx] += isl[v]; while (v != u); } } int ind[MAXN], dp[MAXN]; std::queue<int> q; int main() { std::ios_base::sync_with_stdio(false), std::cin.tie(0); std::cin >> n >> K; for (int i = 2, t; i <= n; ++i) std::cin >> t, g1.adde(t, i); setg(&g1); dfs(1); setg(&g2); tarjan(1); for (int u = 1; u <= n; ++u) for (int i = head[u]; i; i = nxt[i]) if (bel[u] != bel[to[i]]) ++ind[bel[to[i]]], g3.adde(bel[u], bel[to[i]]); setg(&g3); q.push(bel[1]); int ans = 0; while (!q.empty()) { int t = q.front(); q.pop(); dp[t] += val[t]; for (int i = head[t]; i; i = nxt[i]) { if (!--ind[to[i]]) q.push(to[i]); dp[to[i]] = std::max(dp[to[i]], dp[t]); } ans = std::max(ans, dp[t]); } std::cout << ans << std::endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 10; int n, k, fa[N], dep[N], Min[N]; vector<int> e[N]; void dfs(int x) { Min[x] = (e[x].empty() ? 0 : 1e9); for (int v : e[x]) { dep[v] = dep[x] + 1; dfs(v); Min[x] = min(Min[x], Min[v] + 1); } } bool vis[N]; int calc(int x, int res, vector<int> &a) { if (Min[x] > res) return 0; vis[x] = 1; a.push_back(x); int ans = (Min[x] == 0); for (int v : e[x]) ans += calc(v, k - 1, a); return ans; } int solve(int x) { vector<int> a; int ans = calc(x, k, a), Max = 0; if (Min[x] > k) a.push_back(x); for (int u : a) for (int v : e[u]) if (!vis[v]) Max = max(Max, solve(v)); return ans + Max; } int main() { scanf("%d%d", &n, &k); if (n == 1) return puts("0"), 0; for (int i = 2; i <= n; ++i) { scanf("%d", &fa[i]); e[fa[i]].push_back(i); } dfs(1); printf("%d\n", solve(1)); return 0; }
#include <bits/stdc++.h> using namespace std; int n, k, deg[1000005], ar[1000005], jump[1000005], ans[1000005], br[1000005], lr[22][1000005]; vector<int> vr[1000005]; void lca(), dfs1(int), dfs(int, int); int fin(int); queue<int> qr; int main() { scanf("%d %d", &n, &k); for (int i = 2; i < n + 1; i++) { int y; scanf("%d", &y); vr[y].push_back(i); } dfs(1, 0); lca(); for (int i = 1; i < n + 1; i++) ans[i] = i; dfs1(1); for (int i = 1; i < n + 1; i++) { br[i] = i; if (deg[i] == 0) { ar[ans[i]]++; qr.push(i); } } while (!qr.empty()) { int p = qr.front(); qr.pop(); deg[lr[0][p]]--; if (deg[lr[0][p]] == 0) { qr.push(lr[0][p]); } int m = 0; for (int i = 0; i < vr[p].size(); i++) { m = max(m, ar[vr[p][i]]); } ar[p] += m; } cout << ar[1] << " "; } void lca() { for (int j = 1; j < 22; j++) for (int i = 1; i < n + 1; i++) { lr[j][i] = lr[j - 1][lr[j - 1][i]]; } } int fin(int idx, int k) { for (int i = 0; i < 22; i++) { if (k & (1 << i)) { idx = lr[i][idx]; } } if (idx == 0) idx = 1; return idx; } int dr[1000005]; void dfs(int idx, int p) { lr[0][idx] = p; int v = 1e9; for (int i = 0; i < vr[idx].size(); i++) { if (vr[idx][i] == p) continue; deg[idx]++; dfs(vr[idx][i], idx); v = min(v, dr[vr[idx][i]]); } dr[idx] += 1 + (v == 1e9 ? 0 : v); } void dfs1(int idx) { ans[idx] = ans[fin(idx, max(0, k - (dr[idx] - 1)))]; for (int i = 0; i < vr[idx].size(); i++) dfs1(vr[idx][i]); }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 10; int n; int k; int v[2 * N]; int x[2 * N]; int ct; int al[N]; int dp[N][2]; int rk[N]; inline void add(int u, int V) { v[++ct] = V; x[ct] = al[u]; al[u] = ct; } inline void dfs1(int u) { rk[u] = 0x3f3f3f3f; for (int i = al[u]; i; i = x[i]) dfs1(v[i]), rk[u] = min(rk[u], rk[v[i]]); rk[u] = (rk[u] == 0x3f3f3f3f) ? 0 : rk[u] + 1; } inline void dfs(int u) { int son = 0; int del = 0; for (int i = al[u]; i; i = x[i]) { son++; dfs(v[i]); if (rk[v[i]] >= k) { del = max(del, dp[v[i]][1]); } else del = max(del, dp[v[i]][1] - dp[v[i]][0]), dp[u][0] += dp[v[i]][0]; } if (son == 0) dp[u][0] = dp[u][1] = 1; else dp[u][1] = dp[u][0] + del; } int main() { scanf("%d%d", &n, &k); for (int i = 2, f; i <= n; i++) scanf("%d", &f), add(f, i); dfs1(1); dfs(1); printf("%d", dp[1][1]); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 2; int k, dp[N][3], minleaf[N], level[N]; vector<int> adj[N]; void dfs(int x) { if (adj[x].size() == 0) { dp[x][0] = 1; dp[x][1] = 1; minleaf[x] = x; return; } for (int i = 0; i < adj[x].size(); i++) { level[adj[x][i]] = level[x] + 1; dfs(adj[x][i]); if (level[minleaf[adj[x][i]]] - k <= level[x]) { dp[x][0] += dp[adj[x][i]][0]; } if (level[minleaf[adj[x][i]]] < level[minleaf[x]]) { minleaf[x] = minleaf[adj[x][i]]; } } for (int i = 0; i < adj[x].size(); i++) { if (level[minleaf[adj[x][i]]] - k <= level[x]) { dp[x][1] = max(dp[x][0] + dp[adj[x][i]][1] - dp[adj[x][i]][0], dp[x][1]); } else { dp[x][1] = max(dp[x][1], dp[x][0] + dp[adj[x][i]][1]); } } } int main() { level[0] = N; int n, i, j; cin >> n >> k; for (i = 2; i <= n; i++) { cin >> j; adj[j].push_back(i); } dfs(1); cout << max(dp[1][0], dp[1][1]); }
#include <bits/stdc++.h> using namespace std; const int maxn = 1e6 + 5, lg = 20; vector<int> Front_Edge[maxn], Back_Edge[maxn], Component_Front[maxn]; int depth[maxn], Comp[maxn], Leaf_cnt[maxn], Comp_ASS[maxn], dp[maxn]; int par[lg][maxn]; int n, k, Comp_CNT = 1; set<pair<int, int> > Topol_set; stack<int> Rev; void Add_edge(int v, int u) { Front_Edge[v].push_back(u); Back_Edge[u].push_back(v); } void input() { cin >> n >> k; for (int i = 1; i < n; i++) { cin >> par[0][i]; par[0][i]--; Add_edge(par[0][i], i); } } void Update_parents() { for (int i = 1; i < lg; i++) for (int j = 0; j < n; j++) par[i][j] = par[i - 1][par[i - 1][j]]; } void Basic_dfs(int v) { for (auto u : Front_Edge[v]) { depth[u] = depth[v] + 1; Basic_dfs(u); } Rev.push(v); } int Get_to_height(int v, int h) { for (int i = lg - 1; i > -1; i--) if (depth[par[i][v]] >= h) v = par[i][v]; return v; } void Add_Extra_Edges() { for (int i = 1; i < n; i++) if (!Front_Edge[i].size()) Add_edge(i, Get_to_height(i, depth[i] - k)); } void DFS_Back(int v) { for (auto u : Back_Edge[v]) { if (Comp[u]) continue; Comp[u] = Comp[v]; DFS_Back(u); } } void Comp_Decomp() { while (Rev.size()) { int v = Rev.top(); Rev.pop(); if (!Comp[v]) { Comp[v] = Comp_CNT; DFS_Back(v); Comp_CNT++; } } } void Find_ans() { for (int i = 1; i < n; i++) { if (Front_Edge[i].size() == 1 and depth[Front_Edge[i][0]] < depth[i]) Leaf_cnt[Comp[i]]++; } } void Add_Comp_Edge(int c1, int c2) { Component_Front[c1].push_back(c2); Comp_ASS[c2]++; } void Making_comp_tree() { for (int i = 0; i < n; i++) for (auto u : Front_Edge[i]) if (Comp[i] != Comp[u]) Add_Comp_Edge(Comp[i], Comp[u]); } void Making_Topol_Set() { for (int i = 1; i < Comp_CNT; i++) { Topol_set.insert(make_pair(Comp_ASS[i], i)); } } void Dec(int C) { auto A = Topol_set.find(make_pair(Comp_ASS[C], C)); Topol_set.erase(A); Comp_ASS[C]--; Topol_set.insert(make_pair(Comp_ASS[C], C)); } int Updating() { int Ans = 0; while (Topol_set.size()) { pair<int, int> P = *(Topol_set.begin()); Topol_set.erase(Topol_set.begin()); int c = P.second; dp[c] = max(dp[c], Leaf_cnt[c]); Ans = max(Ans, dp[c]); for (auto C : Component_Front[c]) { Dec(C); dp[C] = max(dp[C], Leaf_cnt[C] + dp[c]); } } return Ans; } void solve() { Update_parents(); Basic_dfs(0); Add_Extra_Edges(); Comp_Decomp(); Find_ans(); Making_comp_tree(); Making_Topol_Set(); cout << Updating(); } int main() { ios::sync_with_stdio(false); cout.tie(0); cin.tie(0); input(); solve(); }
#include <bits/stdc++.h> int n, k; std::vector<std::vector<int> > g(1000010); int cnt[1000010] = {0}; int max[1000010] = {0}; int ans = 0; void dfs(int index, int parent) { for (int i = 0; i < g[index].size(); ++i) { int next = g[index][i]; if (next != index) { dfs(next, index); } } if (g[index].size() == 0 && index != 0) { ++cnt[parent]; max[parent] = std::max(max[parent], k - 1); } if (max[index] > 0 && parent != -1) { cnt[parent] += cnt[index]; cnt[index] = 0; max[parent] = std::max(max[parent], max[index] - 1); } } void getans(int index, int parent, int curCnt) { curCnt += cnt[index]; for (int i = 0; i < g[index].size(); ++i) { int next = g[index][i]; if (next != parent) { getans(next, index, curCnt); } } if (curCnt > ans) ans = curCnt; } int main() { std::cin >> n >> k; for (int i = 1; i < n; ++i) { int x; std::cin >> x; --x; g[x].push_back(i); } dfs(0, -1); getans(0, -1, 0); std::cout << ans; }
#include <bits/stdc++.h> using namespace std; const int N = 1E6 + 10; vector<int> adj[N]; int h[N], f[N], g[N]; int n, k; void Read_Input() { scanf("%d%d", &n, &k); for (int u = 2; u <= n; u++) { int p; scanf("%d", &p); adj[p].push_back(u); } } void preDFS(int u, int p) { h[u] = N; f[u] = 0; for (int i = 0; i < adj[u].size(); i++) { int v = adj[u][i]; if (v == p) continue; preDFS(v, u); f[u] += f[v]; h[u] = min(h[u], h[v] + 1); g[u] = max(g[u], g[v] - f[v]); } g[u] += f[u]; if (adj[u].size() == 0 && p != -1) f[u] = 1, h[u] = 0; if (h[u] >= k) f[u] = 0; } void DFS(int u, int p) { for (int i = 0; i < adj[u].size(); i++) { int v = adj[u][i]; if (v == p) continue; DFS(v, u); if (h[u] <= k) g[u] = max(g[u], f[u] - f[v] + g[v]); else g[u] = max(g[u], f[u] + g[v]); } if (adj[u].size() == 0 && p != -1) g[u] = 1; } void Solve() { preDFS(1, -1); printf("%d", g[1]); } int main() { Read_Input(); Solve(); return 0; }
#include <bits/stdc++.h> using namespace std; inline int gi() { int x = 0, f = 1; char ch = getchar(); while (!isdigit(ch)) { if (ch == '-') f = -1; ch = getchar(); } while (isdigit(ch)) { x = (x << 3) + (x << 1) + ch - 48; ch = getchar(); } return x * f; } template <typename T> inline bool Max(T &a, T b) { return a < b ? a = b, 1 : 0; } template <typename T> inline bool Min(T &a, T b) { return b < a ? a = b, 1 : 0; } const int N = 1e6 + 7, inf = 0x3f3f3f3f; int n, edc, K; int head[N], len[N], f[N], g[N]; struct edge { int last, to; edge() {} edge(int last, int to) : last(last), to(to) {} } e[N * 2]; void Add(int a, int b) { e[++edc] = edge(head[a], b), head[a] = edc; e[++edc] = edge(head[b], a), head[b] = edc; } void dfs(int u, int fa) { len[u] = inf; int fg = 1; for (int i = head[u], v = e[i].to; i; i = e[i].last, v = e[i].to) if (v ^ fa) { fg = 0; dfs(v, u); Min(len[u], len[v] + 1); if (len[v] + 1 > K) g[v] = 0; g[u] += g[v]; Max(f[u], f[v] - g[v]); } if (fg) len[u] = 0, g[u] = f[u] = 1; else f[u] += g[u]; } int main() { n = gi(), K = gi(); for (int i = 2; i <= n; ++i) Add(i, gi()); dfs(1, 0); printf("%d\n", f[1]); return 0; }
#include <bits/stdc++.h> template <class Cost = int> struct Edge { int src, dst; Edge(int src = -1, int dst = -1) : src(src), dst(dst){}; }; template <class Cost = int> struct Graph { std::vector<std::vector<Edge<Cost>>> graph; Graph(int n = 0) : graph(n) {} void span(bool direct, int src, int dst) { graph[src].emplace_back(src, dst); if (!direct) graph[dst].emplace_back(dst, src); } int size() const { return graph.size(); } void clear() { graph.clear(); } void resize(int n) { graph.resize(n); } std::vector<Edge<Cost>>& operator[](int v) { return graph[v]; } std::vector<Edge<Cost>> operator[](int v) const { return graph[v]; } }; constexpr int N = 1000000; int par[21][N]; template <class Cost = int> struct LevelAncestor { Graph<Cost> tree; int kmax; void dfs(int v, int p = -1) { par[0][v] = p; for (const auto& e : tree[v]) { if (e.dst == p) continue; dfs(e.dst, v); } } LevelAncestor(const Graph<Cost>& tree, int root) : tree(tree) { kmax = 0; while ((1 << kmax) < (int)tree.size()) ++kmax; dfs(root); for (int k = 1; k <= kmax; ++k) { for (int v = 0; v < (int)tree.size(); ++v) { int p = par[k - 1][v]; par[k][v] = (p == -1 ? -1 : par[k - 1][p]); } } } int climb(int v, int d) const { for (int k = kmax; k >= 0 && v != -1; --k) { if ((1 << k) > d) continue; v = par[k][v]; d -= (1 << k); } return v; } }; void solve() { int n, k; std::cin >> n >> k; Graph<> graph(n); for (int v = 1; v < n; ++v) { int p; std::cin >> p; graph.span(true, --p, v); } std::vector<int> vs; { std::queue<int> que; que.push(0); while (!que.empty()) { int v = que.front(); que.pop(); vs.push_back(v); for (auto e : graph[v]) { que.push(e.dst); } } } auto rvs = vs; std::reverse(rvs.begin(), rvs.end()); std::vector<int> up(n, 0); for (auto v : rvs) { if (graph[v].empty()) { up[v] = k; continue; } for (auto e : graph[v]) { up[v] = std::max(up[v], up[e.dst] - 1); } } std::vector<int> upto(n); { LevelAncestor<> la(graph, 0); for (auto v : vs) { int u = la.climb(v, up[v]); if (u == -1) u = 0; upto[v] = (u == v ? u : upto[u]); } } std::vector<int> szs(n, 0); for (auto v : vs) { if (graph[v].empty()) ++szs[upto[v]]; } for (auto v : rvs) { int max = 0; for (auto e : graph[v]) max = std::max(max, szs[e.dst]); szs[v] += max; } std::cout << szs[0] << "\n"; } int main() { std::cin.tie(nullptr); std::ios::sync_with_stdio(false); solve(); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000005; const int inf = numeric_limits<int>::max(); vector<int> t[N]; int dp[N][2], mn[N], d[N], n, k, v; int dfs0(int v, int dt) { d[v] = dt; mn[v] = inf; if (t[v].empty()) return mn[v] = dt; for (auto u : t[v]) mn[v] = min(mn[v], dfs0(u, dt + 1)); return mn[v]; } void dfs1(int v) { if (t[v].empty()) return void(dp[v][0] = dp[v][1] = 1); int sum = 0, ans = 0; for (auto u : t[v]) { dfs1(u); if (mn[u] - d[v] <= k) { sum += dp[u][0]; ans = max(ans, dp[u][1] - dp[u][0]); } else ans = max(ans, dp[u][1]); } dp[v][0] = sum; dp[v][1] = sum + ans; } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); cin >> n >> k; for (int i = 2; i <= n; i++) { cin >> v; t[v].push_back(i); } dfs0(1, 0); dfs1(1); cout << dp[1][1] << endl; }
#include <bits/stdc++.h> using namespace std; long long ans = 0; const int N = 1e6 + 6; vector<int> adj[N]; int INF = 1e9, k; int t[N], sum[N]; void dfs(int u, int p) { for (auto v : adj[u]) if (v != p) { dfs(v, u); if (t[v] + 1 <= k) sum[u] += sum[v]; t[u] = min(t[u], t[v] + 1); } if (t[u] == INF) t[u] = 0, sum[u] = 1; } int solve(int u, int p) { int ret = 0; for (auto v : adj[u]) if (v != p) { if (t[v] + 1 <= k) ret = max(ret, sum[u] - sum[v] + solve(v, u)); else ret = max(ret, sum[u] + solve(v, u)); } if (t[u] == 0) ret = 1; return ret; } int main() { ios_base::sync_with_stdio(0); cin.tie(0); int n; cin >> n >> k; for (int i = 1; i <= n; i++) t[i] = INF; for (int i = 2; i <= n; i++) { int x; cin >> x; adj[i].push_back(x); adj[x].push_back(i); } dfs(1, 1); cout << solve(1, 1) << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 1002000; int n, k, fa[maxn]; vector<int> g[maxn]; int dep[maxn], minn[maxn]; int f[maxn], d[maxn]; void read() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; i++) { scanf("%d", &fa[i]); g[fa[i]].push_back(i); } } void dfs(int now, int dp) { dep[now] = dp; if (g[now].size() == 0) { minn[now] = dp; return; } minn[now] = 1e8; for (int i = 0; i < g[now].size(); i++) { dfs(g[now][i], dp + 1); minn[now] = min(minn[now], minn[g[now][i]]); } } void dfs2(int now) { if (g[now].size() == 0) { f[now] = d[now] = 1; return; } for (int i = 0; i < g[now].size(); i++) dfs2(g[now][i]); for (int i = 0; i < g[now].size(); i++) if (minn[g[now][i]] - dep[now] <= k) d[now] += d[g[now][i]]; for (int i = 0; i < g[now].size(); i++) { if (minn[g[now][i]] - dep[now] <= k) f[now] = max(f[now], d[now] - d[g[now][i]] + f[g[now][i]]); else f[now] = max(f[now], d[now] + f[g[now][i]]); } } void work() { dfs(1, 1); dfs2(1); printf("%d\n", f[1]); } int main() { read(); work(); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 5; vector<int> gfo[N]; int p[N], here[N]; bool vst[N]; int find(int u) { if (u == p[u]) return u; return p[u] = find(p[u]); } void uni(int u, int v) { int pu = find(u); int pv = find(v); p[pv] = pu; } void up(int u, int k) { while (k && p[u] == u) { uni(here[u], u); u = here[u]; k--; if (u == 0) break; } } int dfs(int u) { int ans = 0; for (int v : gfo[u]) ans = max(ans, dfs(v)); return ans + here[u]; } int main() { int n; scanf("%d", &n); int k; scanf("%d", &k); for (int i = int(1); i < int(n); ++i) { int pa; scanf("%d", &pa); pa--; gfo[pa].push_back(i); here[i] = pa; } vector<int> leafs; queue<int> q; q.push(0); while (!q.empty()) { int u = q.front(); q.pop(); for (int v : gfo[u]) { if (int(gfo[v].size()) == 0) leafs.push_back(v); q.push(v); } } for (int i = int(0); i < int(n); ++i) p[i] = i; for (int u : leafs) up(u, k); for (int i = int(0); i < int(n); ++i) find(i); memset(here, 0, sizeof(here)); for (int i = int(0); i < int(n); ++i) if (int(gfo[i].size()) == 0) here[p[i]]++; printf("%d\n", dfs(0)); return 0; }
#include <bits/stdc++.h> int debugnum = 0; using namespace std; const int MAXN = 1e6 + 50; vector<int> arc[MAXN]; int DFS(int K, int pos, int &depth, int &score1, int &score2) { if (arc[pos].size() == 0) { depth = score1 = score2 = 1; return 0; } depth = INT_MAX >> 1; score1 = 0; score2 = 0; for (int i = (0); i < (arc[pos].size()); i++) { int e = arc[pos][i]; int dep, s1, s2; DFS(K, e, dep, s1, s2); if (dep <= K) { depth = min(depth, dep); score1 += s1; score2 = max(score2, s2 - s1); } else score2 = max(score2, s2); } depth++; score2 += score1; return 0; } int main() { int N, M, K; while (cin >> N >> K) { for (int i = (0); i < (N + 5); i++) arc[i].clear(); for (int b = (2); b < (N + 1); b++) { int a; scanf("%d", &a); arc[a].push_back(b); } int depth, score1, score2; DFS(K, 1, depth, score1, score2); cout << score2 << endl; } return 0; }
#include <bits/stdc++.h> const int INF = 0x3f3f3f3f; const int MAX_N = 1e6 + 7; int n, k; std::vector<int> gr[MAX_N]; std::pair<int, int> drev[MAX_N]; int d[MAX_N]; int pre[2][MAX_N], dep[MAX_N], po = 0; int dfs(const int& cur, const int& depth) { pre[0][cur] = po++; dep[cur] = depth; for (const auto& nei : gr[cur]) dfs(nei, depth + 1); pre[1][cur] = po; return 0; } int go(const int& cur) { if (pre[0][cur] + 1 == pre[1][cur]) { drev[cur].first = dep[cur] - k; drev[cur].second = 1; return 0; } drev[cur].first = INF; for (const auto& nei : gr[cur]) { go(nei); drev[cur].first = std::min(drev[cur].first, drev[nei].first); if (drev[nei].first <= dep[cur]) drev[cur].second += drev[nei].second; } return 0; } int despacito(const int& cur) { if (pre[0][cur] + 1 == pre[1][cur]) { return d[cur] = 1; } d[cur] = drev[cur].second; for (const auto& nei : gr[cur]) { despacito(nei); d[cur] = std::max(d[cur], drev[cur].second - (drev[nei].first <= dep[cur] ? drev[nei].second : 0) + d[nei]); } return d[cur]; } int main(void) { std::ios::sync_with_stdio(0); std::cin.tie(0); std::cin >> n >> k; for (int i = 1, p; i < n; ++i) { std::cin >> p; gr[p - 1].push_back(i); } std::cout << (dfs(0, 0) + go(0) + despacito(0)) << "\n"; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000005; int n, k, ans, e[N], ec, nx[N], fi[N], d[N], f[N], g[N]; bool vis[N]; void adde(int u, int v) { e[++ec] = v; nx[ec] = fi[u]; fi[u] = ec; } void dfs(int u, int d) { g[u] = 1e9; if (!vis[u]) { g[u] = d; f[u] = 1; } int mx = 0; for (int i = fi[u]; i; i = nx[i]) { int v = e[i]; dfs(v, d + 1); g[u] = min(g[u], g[v]); if (g[v] - d <= k) { f[u] += f[v]; f[v] = 0; } } } int work(int u) { int mx = 0; for (int i = fi[u]; i; i = nx[i]) mx = max(mx, work(e[i])); return f[u] + mx; } int main() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; ++i) { int fa; scanf("%d", &fa); adde(fa, i); vis[fa] = true; } dfs(1, 0); printf("%d\n", work(1)); return 0; }
#include <bits/stdc++.h> #pragma GCC optimize("Ofast") using namespace std; const long double eps = 1e-7; const int inf = 1000000010; const long long INF = 10000000000000010LL; const int mod = 1000000007; const int MAXN = 1000010, LOG = 20; int n, m, k, u, v, x, y, t, a, b, ans; int par[MAXN][LOG]; int leaf[MAXN]; int comp[MAXN]; int sz[MAXN]; int dp[MAXN]; bitset<MAXN> mark; vector<int> Gin[MAXN], Gout[MAXN]; vector<int> G[MAXN]; vector<int> vec; int getpar(int v) { for (int i = 0; i < LOG; i++) if ((1 << i) & k) v = par[v][i]; return v; } void dfsout(int node) { mark[node] = 1; for (int v : Gout[node]) if (!mark[v]) dfsout(v); vec.push_back(node); } void dfsin(int node, int c) { comp[node] = c; for (int v : Gin[node]) if (!comp[v]) dfsin(v, c); } int f(int node) { if (dp[node] != -1) return dp[node]; dp[node] = 0; for (int v : G[node]) dp[node] = max(dp[node], f(v)); return dp[node] += sz[node]; } int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); memset(dp, -1, sizeof(dp)); cin >> n >> k; fill(leaf + 2, leaf + n + 1, 1); for (int i = 2; i <= n; i++) { cin >> par[i][0]; leaf[par[i][0]] = 0; Gout[par[i][0]].push_back(i); Gin[i].push_back(par[i][0]); } par[1][0] = 1; for (int j = 1; j < LOG; j++) { par[1][j] = 1; for (int i = 2; i <= n; i++) par[i][j] = par[par[i][j - 1]][j - 1]; } for (int i = 2; i <= n; i++) if (leaf[i]) { int p = getpar(i); Gin[p].push_back(i); Gout[i].push_back(p); } dfsout(1); reverse(vec.begin(), vec.end()); for (int i : vec) if (!comp[i]) dfsin(i, i); for (int i = 1; i <= n; i++) sz[comp[i]] += leaf[i]; for (int i = 1; i <= n; i++) { for (int v : Gout[i]) if (comp[i] != comp[v]) G[comp[i]].push_back(comp[v]); } cout << f(1) << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000005; int n, k, u, f[N], g[N], h[N]; vector<int> adj[N]; void DFS(int u) { if (adj[u].empty()) { f[u] = g[u] = 1; h[u] = k; } for (int &v : adj[u]) { DFS(v); if (h[v] > 0) { g[u] += g[v]; h[u] = max(h[u], h[v] - 1); } } for (int &v : adj[u]) if (h[v] > 0) f[u] = max(f[u], g[u] - g[v] + f[v]); else f[u] = max(f[u], g[u] + f[v]); } int main() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; i++) { scanf("%d", &u); adj[u].push_back(i); } DFS(1); printf("%d", max(f[1], g[1])); }
#include <bits/stdc++.h> using namespace std; const long double PI = acos(-1); const long double eps = 0.0000000001; const long long INF = 0x3fffffffffffffff; long long n, k, fa[1000005], depth[1000005], low[1000005], canback[1000005], cantback[1000005]; vector<long long> son[1000005]; void dfs1(long long now) { for (long long i = 0; i < (long long)son[now].size(); ++i) { depth[son[now][i]] = depth[now] + 1; dfs1(son[now][i]); } } void dfs2(long long now) { if (!son[now].size()) { low[now] = now; } for (long long i = 0; i < (long long)son[now].size(); ++i) { dfs2(son[now][i]); if (depth[low[now]] > depth[low[son[now][i]]]) { low[now] = low[son[now][i]]; } } } void dfs3(long long now) { if (!son[now].size()) { canback[now] = 1; } for (long long i = 0; i < (long long)son[now].size(); ++i) { dfs3(son[now][i]); if (depth[low[son[now][i]]] - depth[now] <= k) { canback[now] += canback[son[now][i]]; } } } void dfs4(long long now) { cantback[now] = canback[now]; for (long long i = 0; i < (long long)son[now].size(); ++i) { dfs4(son[now][i]); if (depth[low[son[now][i]]] - depth[now] <= k) { cantback[now] = max(cantback[now], canback[now] - canback[son[now][i]] + cantback[son[now][i]]); } else { cantback[now] = max(cantback[now], canback[now] + cantback[son[now][i]]); } } } signed main() { depth[0] = INF; ios::sync_with_stdio(false); cin >> n >> k; for (long long i = 2; i <= n; ++i) { cin >> fa[i]; son[fa[i]].push_back(i); } dfs1(1); dfs2(1); dfs3(1); dfs4(1); cout << cantback[1] << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int tot, fa[1000005][20], in[1000005], ans, dp[1000005], st[1000005], hd, cl, x, n, k, i, j, deg[1000005], dfn[1000005], low[1000005], sum[1000005], col[1000005], vis[1000005]; vector<int> son[1000005], to[1000005]; queue<int> q; void add(int x, int y) { son[x].push_back(y); } inline int find(int x, int y) { for (int i = 19; ~i; --i) if ((y >> i) & 1) x = fa[x][i]; return x; } void tarjan(int now) { dfn[now] = low[now] = ++tot; st[++hd] = now; vis[now] = 1; for (int T, i = 0; i < son[now].size(); ++i) { if (!dfn[T = son[now][i]]) tarjan(T), low[now] = min(low[now], low[T]); else if (vis[T]) low[now] = min(low[now], low[T]); } if (low[now] == dfn[now]) { ++cl; while (now != st[hd + 1]) { sum[cl] += in[st[hd]]; vis[st[hd]] = 0; col[st[hd]] = cl; --hd; } } } int main() { cin >> n >> k; for (i = 2; i <= n; ++i) cin >> fa[i][0], ++in[fa[i][0]], add(fa[i][0], i); fa[1][0] = 1; for (i = 1; i <= 19; ++i) for (j = 1; j <= n; ++j) fa[j][i] = fa[fa[j][i - 1]][i - 1]; for (i = 1; i <= n; in[i] = (in[i] == 0), ++i) if (!in[i]) add(i, find(i, k)); tarjan(1); for (i = 1; i <= n; ++i) { for (j = 0; j < son[i].size(); ++j) { if (col[son[i][j]] != col[i]) { to[col[i]].push_back(col[son[i][j]]); ++deg[col[son[i][j]]]; } } } for (i = 1; i <= cl; ++i) if (!deg[i]) q.push(i); while (q.size()) { x = q.front(); q.pop(); dp[x] += sum[x]; ans = max(ans, dp[x]); for (i = 0; i < to[x].size(); ++i) { if (!--deg[to[x][i]]) q.push(to[x][i]); dp[to[x][i]] = max(dp[to[x][i]], dp[x]); } } cout << ans; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 100; vector<int> E[N]; int cnt[2 * N] = {0}, c[N]; int k; int ans[N], dis[N], dcnt[N]; int uu[N]; int dfs(int u, int dep) { int cc = cnt[dep + k + 1], sum = (u != 1 && c[u] == 1), mx = 0, mm = 0, sm = 0; if (u != 1 && c[u] == 1) cnt[dep]++; for (int v : E[u]) { sum += dfs(v, dep + 1); if (dis[v] > 0) { sm += dcnt[v] - uu[v]; mx = max(mx, ans[v] - dcnt[v]); } else mx = max(mx, ans[v] - uu[v]); mm = max(mm, dis[v] - 1); } int cur = sum - (cnt[dep + k + 1] - cc); dis[u] = mm; dcnt[u] = sm + cur; ans[u] = mx + cur + sm; if (u != 1 && c[u] == 1) dis[u] = k; return cur; } int dfs2(int u, int dep) { int cc = cnt[dep + k], sum = (u != 1 && c[u] == 1); if (u != 1 && c[u] == 1) cnt[dep]++; for (int v : E[u]) { sum += dfs2(v, dep + 1); } int cur = sum - (cnt[dep + k] - cc); uu[u] = cur; return cur; } int main() { int n; scanf("%d%d", &n, &k); if (n == 1) { puts("1"); return 0; } for (int i = 2; i <= n; i++) { int pa; scanf("%d", &pa); E[pa].push_back(i); c[pa]++; c[i]++; } dfs2(1, 0); memset(cnt, 0, sizeof cnt); dfs(1, 0); printf("%d\n", ans[1]); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 100; vector<int> a[N]; int deep[N], leaf[N], dp[N], n, k; void dfs(int u) { if (a[u].size() == 0) { leaf[u] = dp[u] = deep[u] = 1; return; } deep[u] = n + 12; int tmp = 0; for (int v : a[u]) { dfs(v); deep[u] = min(deep[v] + 1, deep[u]); tmp += leaf[v]; } if (deep[u] <= k) leaf[u] = tmp; for (int v : a[u]) { dp[u] = max(dp[u], tmp - leaf[v] + dp[v]); } } int x; int main() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; ++i) { scanf("%d", &x); a[x].push_back(i); } dfs(1); printf("%d", dp[1]); return 0; }
#include <bits/stdc++.h> #pragma GCC optimize("Ofast") using namespace std; const long long infl = 2e18; const long long infi = 1e9; const long long mod = 998244353; mt19937 rang(chrono::high_resolution_clock::now().time_since_epoch().count()); auto clk = clock(); long long rng(long long lim) { uniform_int_distribution<long long> uid(0, lim - 1); return uid(rang); } long long p[1000005]; long long dp[1000005][2]; long long leafy[1000005]; vector<long long> gra[1000005]; long long tot[1000005]; long long n, k; void dfs(long long fr, long long at) { if (gra[at].empty()) tot[at] = 1; else { leafy[at] = infi; for (long long i : gra[at]) { dfs(at, i); leafy[at] = min(leafy[at], leafy[i] + 1); tot[at] += tot[i]; } } } void dfs(long long at) { long long mm = 0; if (gra[at].empty()) { dp[at][0] = 1; dp[at][1] = 1; return; } for (long long i : gra[at]) { dfs(i); if (leafy[i] < k) { dp[at][0] += dp[i][0]; mm = max(mm, dp[i][1] - dp[i][0]); } else mm = max(mm, dp[i][1]); } dp[at][1] = dp[at][0] + mm; } void solve() { cin >> n >> k; if (n == 1) { cout << 0 << '\n'; return; } for (long long i = 2; i <= n; i++) { cin >> p[i]; gra[p[i]].push_back(i); } dfs(1, 1); dfs(1); cout << dp[1][1] << '\n'; } signed main() { ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0); srand(chrono::high_resolution_clock::now().time_since_epoch().count()); cout << fixed << setprecision(10); long long t = 1; while (t--) solve(); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000005; struct ab { int f, t; } t[N << 1]; int h, hh[N], d[N], dmn[N], sum[N], dp[N], k; void make(int x, int y) { t[++h].f = hh[x]; t[h].t = y; hh[x] = h; } void dfs(int x, int y) { d[x] = d[y] + 1; dmn[x] = N; int flag = 0; for (int i = hh[x]; i; i = t[i].f) { int j = t[i].t; if (j == y) continue; flag = 1; dfs(j, x); dmn[x] = min(dmn[x], dmn[j]); if (dmn[j] - d[x] <= k) sum[x] += sum[j], dp[j] -= sum[j]; dp[x] = max(dp[x], dp[j]); } if (!flag) dmn[x] = d[x], sum[x] = 1; dp[x] += sum[x]; } int main() { int n; scanf("%d%d", &n, &k); for (int i = 2; i <= n; i++) { int x; scanf("%d", &x); make(x, i), make(i, x); } dfs(1, 0); printf("%d\n", dp[1]); return 0; }
#include <bits/stdc++.h> using namespace std; int n, k, dep[2000010], mn[2000010], f[2000010][2]; vector<int> v[2000010]; void dfs(int p, int fa) { dep[p] = dep[fa] + 1; if (v[p].size() == 1 && p != 1) mn[p] = dep[p], f[p][0] = f[p][1] = 1; else mn[p] = 1e9; int t = 0; for (int i : v[p]) if (i != fa) dfs(i, p), mn[p] = min(mn[p], mn[i]), f[p][1] += f[i][1], t += f[i][1]; for (int i : v[p]) if (i != fa) f[p][0] = max(f[p][0], t - f[i][1] + f[i][0]); if (mn[p] >= dep[p] + k) f[p][1] = 0; } int main() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; i++) { int x; scanf("%d", &x); v[x].push_back(i), v[i].push_back(x); } dfs(1, 0); printf("%d\n", f[1][0]); return 0; }
#include <bits/stdc++.h> using namespace std; const int MAXN = 1000005; vector<int> g[MAXN]; int val_at_v[MAXN]; int ans = 0; pair<int, int> dfs(int v, int k, vector<int> &path) { path.push_back(v); int min_depth_subtr = MAXN; int max_subtr = 0; if (g[v].empty()) { val_at_v[v] = 1; min_depth_subtr = 0; } for (auto to : g[v]) { auto subtr = dfs(to, k, path); max_subtr = max(max_subtr, subtr.first); min_depth_subtr = min(min_depth_subtr, subtr.second + 1); } if (min_depth_subtr < k) { int cnt_up = min(k - min_depth_subtr, (int)path.size() - 1); if (cnt_up) { val_at_v[*(path.rbegin() + cnt_up)] += val_at_v[v]; val_at_v[v] = 0; } } path.pop_back(); ans = max(ans, max_subtr + val_at_v[v]); return {max_subtr + val_at_v[v], min_depth_subtr}; } int main() { int n, k; scanf("%d%d", &n, &k); for (int i = 2; i <= n; ++i) { int p_i; scanf("%d", &p_i); g[p_i].push_back(i); } vector<int> path; dfs(1, k, path); cout << ans << "\n"; return 0; }
#include <bits/stdc++.h> using namespace std; long long power(long long a, long long b, long long md) { return (!b ? 1 : (b & 1 ? a * power(a * a % md, b / 2, md) % md : power(a * a % md, b / 2, md) % md)); } const int xn = 1e6 + 10; const int xm = 20; const int sq = 320; const int inf = 1e9 + 10; const long long INF = 1e18 + 10; const int mod = 998244353; const int base = 257; int n, k, dp[xn], par[xm][xn], c, ptr, col[xn]; pair<int, int> E[xn + xn]; vector<int> adj[2][xn], G[xn], topo; bool mark[xn], leaf[xn]; void add_edge(int v, int u) { adj[0][v].push_back(u); adj[1][u].push_back(v); E[ptr++] = {v, u}; } void DFS(int v) { mark[v] = true; for (int u : adj[0][v]) if (!mark[u]) DFS(u); topo.push_back(v); } void SFD(int v, int x) { mark[v] = true; col[v] = x; dp[x] += leaf[v]; for (int u : adj[1][v]) if (!mark[u]) SFD(u, x); } int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); ; cin >> n >> k; memset(leaf, true, sizeof leaf); for (int i = 2; i <= n; ++i) { cin >> par[0][i]; add_edge(par[0][i], i); leaf[par[0][i]] = false; } par[0][1] = 1; for (int i = 1; i < xm; ++i) for (int v = 1; v <= n; ++v) par[i][v] = par[i - 1][par[i - 1][v]]; for (int i = 1; i <= n; ++i) { if (!leaf[i]) continue; int v = i, d = k; for (int i = xm - 1; i >= 0; --i) if ((1 << i) <= d) v = par[i][v], d -= (1 << i); add_edge(i, v); } for (int i = 1; i <= n; ++i) if (!mark[i]) DFS(i); memset(mark, false, sizeof mark); reverse(topo.begin(), topo.end()); for (int v : topo) if (!mark[v]) SFD(v, ++c); for (int i = 0; i < ptr; ++i) { int v = E[i].first, u = E[i].second; if (col[v] != col[u]) G[col[v]].push_back(col[u]); } for (int v = c; v >= 1; --v) { int mx = 0; for (int u : G[v]) mx = max(mx, dp[u]); dp[v] += mx; } cout << dp[col[1]] << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; auto const Random_Address = [] { char* c; c = new char; delete c; return uint64_t(c); }; uint64_t const SEED = chrono::steady_clock::now().time_since_epoch().count() * (Random_Address() bitor 1); mt19937 Rng(SEED); constexpr int Mask(int i) { return 1 << i; } constexpr int Getb(int x, int i) { return x >> i bitand 1; } template <size_t N> bitset<N> Bits(int x) { return bitset<N>(x); } template <class X, class Y> bool minimize(X& x, Y const& y) { return y < x ? x = y, 1 : 0; } template <class X, class Y> bool maximize(X& x, Y const& y) { return y > x ? x = y, 1 : 0; } int const maxN = 1e6; int const maxK = 1e6; int const infi = 1e9 + 7; int N, K; vector<int> adj[maxN + 3]; int f[maxN + 3], g[maxN + 3], h[maxN + 3], d[maxN + 3]; void dfs(int u) { if (adj[u].empty()) { h[u] = d[u]; f[u] = g[u] = 1; return; } int _max = 0; h[u] = infi; for (int v : adj[u]) { d[v] = d[u] + 1; dfs(v); minimize(h[u], h[v]); if (h[v] - d[u] <= K) { f[u] += f[v]; g[u] += f[v]; maximize(_max, g[v] - f[v]); } else maximize(_max, g[v]); } g[u] += _max; return; } int main() { cin.tie(nullptr)->sync_with_stdio(false); cin >> N >> K; for (int v = 2; v <= N; v++) { int u; cin >> u; adj[u].push_back(v); } dfs(1); cout << g[1]; return 0; }
#include <bits/stdc++.h> using namespace std; const long double eps = 1e-13; const long double PI = acos(-1); const int INF = (int)1e9; const long long INFF = (long long)1e18; const int mod = (int)1e9 + 7; const int MXN = (int)1e6 + 7; int n, k; vector<int> edge[MXN]; vector<int> re_edge[MXN]; int prt[MXN]; int dp[21][MXN]; void init() { scanf("%d %d", &n, &k); for (int i = 2; i < n + 1; i++) { scanf("%d", prt + i); edge[prt[i]].push_back(i); re_edge[i].push_back(prt[i]); dp[0][i] = prt[i]; } return; } bool leaf[MXN]; struct Scc { int re[MXN], cntp; int in[MXN]; int siz[MXN], gp[MXN]; int num[MXN]; int val[MXN]; int fd(int u) { return gp[u] == u ? u : gp[u] = fd(gp[u]); } void uni(int u, int v) { u = fd(u), v = fd(v); if (u == v) return; if (siz[u] > siz[v]) swap(u, v); gp[u] = v; siz[u] += siz[v]; return; } void dfs(int u) { in[u] = 1; for (int v : edge[u]) { if (!in[v]) dfs(v); } re[++cntp] = u; return; } void dfs2(int u, int la) { in[u] = 1; uni(u, la); for (int v : re_edge[u]) { if (!in[v]) dfs2(v, la); } } void pre() { for (int i = 1; i < n + 1; i++) siz[i] = 1, gp[i] = i; for (int i = 1; i < n + 1; i++) if (!in[i]) dfs(i); memset(in, 0, sizeof(in)); ; for (int i = n; i >= 1; i--) if (!in[re[i]]) dfs2(re[i], re[i]); for (int i = 1; i < n + 1; i++) if (leaf[i]) { num[fd(i)]++; val[fd(i)]++; } return; } int solve() { pre(); int ans = 0; for (int i = 1; i < n + 1; i++) { ans = max(ans, val[fd(i)]); for (int v : edge[re[i]]) { int p1 = fd(v); int p2 = fd(re[i]); if (p1 == p2) continue; val[p2] = max(val[p2], num[p2] + val[p1]); ans = max(ans, val[p2]); } } return ans; } } scc; int dep[MXN]; void dfs(int u, int dpt) { dep[u] = dpt; for (int v : edge[u]) dfs(v, dpt + 1); return; } int up(int u, int d) { for (int i = 0; i < 21; i++) { if (d & (1 << i)) { u = dp[i][u]; } } return u; } void sol() { dfs(1, 1); for (int i = 1; i < 21; i++) for (int j = 1; j < n + 1; j++) { dp[i][j] = dp[i - 1][dp[i - 1][j]]; } for (int i = 1; i < n + 1; i++) if (edge[i].empty()) { leaf[i] = 1; int p = 0; if (dep[i] <= k) p = 1; else p = up(i, k); edge[i].push_back(p); re_edge[p].push_back(i); } int ans = scc.solve(); printf("%d\n", ans); return; } int main(void) { init(); sol(); return 0; }
#include <bits/stdc++.h> #pragma GCC optimize("O2") using namespace std; const long long MXN = 1e6 + 10; long long n, k, x; long long Comp[MXN], Cnt[MXN], dp[MXN]; vector<long long> adj[MXN], adt[MXN], G[MXN], V[MXN], Jad, Top; bool mark[MXN], vis[MXN]; void dfs1(long long u, long long d) { if (G[u].empty()) { adj[u].push_back(Jad[max(d - k, 0ll)]), adt[Jad[max(d - k, 0ll)]].push_back(u); } Jad.push_back(u); for (auto v : G[u]) dfs1(v, d + 1); Jad.pop_back(); } void dfs(long long u) { mark[u] = 1; for (auto v : adj[u]) { if (!mark[v]) dfs(v); } Top.push_back(u); } void sfd(long long u) { vis[u] = 1, Comp[u] = x, Cnt[x] += (G[u].empty()), V[x].push_back(u); for (auto v : adt[u]) { if (!vis[v]) sfd(v); } } int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n >> k; for (int i = 2; i <= n; i++) cin >> x, adj[x].push_back(i), adt[i].push_back(x), G[x].push_back(i); dfs1(1, 0), x = 1; for (int i = 1; i <= n; i++) { if (!mark[i]) dfs(i); } reverse(Top.begin(), Top.end()); for (auto u : Top) { if (!vis[u]) sfd(u), x++, dp[x - 1] = Cnt[x - 1]; } for (int c = x - 1; c; c--) { for (auto u : V[c]) { for (auto v : adj[u]) { if (Comp[v] != c) dp[c] = max(dp[c], Cnt[c] + dp[Comp[v]]); } } } cout << dp[Comp[1]] << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; int power(int x, int y) { int res = 1; while (y) { if (y & 1) res = (res * x) % 1000000007; y = y / 2, x = (x * x) % 1000000007; } return res % 1000000007; } pair<int, int> dp[1000001]; int ans[1000001]; int n, k; vector<vector<int> > arr(1000001); int depth[1000001]; void dfs(int u, int par) { dp[u] = make_pair(n + 1, 0); int i; bool poss = true; for (i = 0; i < arr[u].size(); i++) { int v = arr[u][i]; if (v != par) { depth[v] = 1 + depth[u]; dfs(v, u); if (dp[v].first <= depth[u]) { dp[u].first = min(dp[u].first, dp[v].first); dp[u].second += dp[v].second; } poss = false; } } if (poss) dp[u] = make_pair(depth[u] - k, 1); } void dfs1(int u, int par) { bool poss = true; int i; for (i = 0; i < arr[u].size(); i++) { int v = arr[u][i]; if (v != par) { dfs1(v, u); int temp = dp[u].second; if (dp[v].first <= depth[u]) temp -= dp[v].second; ans[u] = max(ans[u], temp + ans[v]); poss = false; } } if (poss) ans[u] = 1; } signed main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin >> n >> k; int i; if (n == 1) { cout << 0; return 0; } for (i = 0; i < n - 1; i++) { int p; cin >> p; arr[p].push_back(i + 2); arr[i + 2].push_back(p); } dfs(1, 0); dfs1(1, 0); cout << ans[1]; }
#include <bits/stdc++.h> using namespace std; int n, k, siz[1000005], dep[1000005], low[1000005], f[1000005]; bool is_leaf[1000005]; vector<int> G[1000005]; inline int read() { int x = 0, f = 1; char ch = getchar(); while (!isdigit(ch)) { if (ch == '-') f = -1; ch = getchar(); } while (isdigit(ch)) { (x *= 10) += ch - '0'; ch = getchar(); } return x * f; } void dfs1(int u, int c_fa) { dep[u] = dep[c_fa] + 1; low[u] = 2e9; if (is_leaf[u]) low[u] = dep[u]; for (int v : G[u]) dfs1(v, u), low[u] = min(low[u], low[v]); } void dfs2(int u) { if (is_leaf[u]) siz[u] = 1; for (int v : G[u]) { dfs2(v); if (low[v] - dep[u] <= k) siz[u] += siz[v], siz[v] = 0; } } void dfs3(int u) { f[u] = siz[u]; int mx = 0; for (int v : G[u]) dfs3(v), mx = max(mx, f[v]); f[u] += mx; } int main() { n = read(), k = read(); memset(is_leaf, true, sizeof(is_leaf)); for (int i = 2, x; i <= n; i++) x = read(), is_leaf[x] = false, G[x].push_back(i); dfs1(1, 0); dfs2(1); dfs3(1); printf("%d\n", f[1]); return 0; }
#include <bits/stdc++.h> using namespace std; const int INF = 1e9 + 7; int n, k; int dp[1000005], dpe[1000005]; int md[1000005]; vector<int> G[1000005]; void dfs(int v, int cd) { if (G[v].empty()) { md[v] = cd; dp[v] = 1; return; } md[v] = INF; for (int i = 0; i < (G[v].size()); i++) { int u = G[v][i]; dfs(u, cd + 1); md[v] = min(md[v], md[u]); if (md[u] <= cd + k) { dp[v] += dp[u]; dpe[v] = max(dpe[v], dpe[u] - dp[u]); } else dpe[v] = max(dpe[v], dpe[u]); } dpe[v] += dp[v]; } int main() { scanf("%d%d", &n, &k); for (int i = 0; i < (n - 1); i++) { int v; scanf("%d", &v); G[v].push_back(i + 2); } dfs(1, 0); int ans = 0; for (int i = 1; i <= (n); i++) ans = max(ans, dpe[i]); printf("%d\n", ans); return 0; }
#include <bits/stdc++.h> using namespace std; struct ss { int next, to; } e[1000005 << 1]; int cnt, head[1000005]; inline void add(int x, int y) { e[++cnt].next = head[x]; e[cnt].to = y; head[x] = cnt; } int n, k, vis[1000005], low[1000005], siz[1000005], dep[1000005]; inline void dfs2(int now, int d) { dep[now] = d; low[now] = 1 << 30; if (!vis[now]) low[now] = d; for (int i = head[now]; i; i = e[i].next) { int v = e[i].to; dfs2(v, d + 1); low[now] = min(low[now], low[v]); } } inline void dfs3(int now) { if (!vis[now]) siz[now] = 1; for (int i = head[now]; i; i = e[i].next) { int v = e[i].to; dfs3(v); if (low[v] - dep[now] <= k) { siz[now] += siz[v]; siz[v] = 0; } } } inline int dfs1(int now) { int s = 0; for (int i = head[now]; i; i = e[i].next) s = max(s, dfs1(e[i].to)); return s + siz[now]; } int main() { cin >> n >> k; for (int i = 2; i <= n; i++) { int x; cin >> x; add(x, i); vis[x] = 1; } dfs2(1, 0); dfs3(1); cout << dfs1(1); }
#include <bits/stdc++.h> using namespace std; const int N = 1000003; const int M = N << 1; const int INF = 2e9; int n, K; int cnt, head[N], Next[M], v[M]; int b[N]; long long w[N]; int pre[N], dfn[N], clo, kth[N], s[N]; int mn[N], dep[N]; int top[N]; void read(int &x) { char ch = getchar(); x = 0; int w = 0; for (; ch < '0' || ch > '9'; ch = getchar()) w |= (ch == '-'); for (; ch >= '0' && ch <= '9'; ch = getchar()) x = (x << 3) + (x << 1) + ch - '0'; if (w) x = -x; } void add(int x, int y) { Next[++cnt] = head[x]; head[x] = cnt; v[cnt] = y; } int predfs(int x, int fa, int d) { s[d] = x; dep[x] = d; if (d - K > 0) kth[x] = s[d - K]; else kth[x] = 1; if (!head[x]) mn[x] = x; for (int i = head[x]; i; i = Next[i]) { int val = predfs(v[i], x, d + 1); if (dep[val] < dep[mn[x]]) mn[x] = val; } return mn[x]; } void dfs(int x, int fa) { long long mx = 0; for (int i = head[x]; i; i = Next[i]) if (v[i] != fa) { dfs(v[i], x); mx = max(mx, w[v[i]]); } w[x] += mx; } int getop(int x) { if (top[x]) return top[x]; int y = mn[kth[x]]; if (dep[y] == dep[x]) return top[x] = kth[x]; else return top[x] = getop(y); } int main() { read(n); read(K); int x; for (int i = (2); i <= (n); i++) { read(x); add(x, i); } dep[0] = INF; predfs(1, 0, 0); for (int i = (1); i <= (n); i++) if (!head[i]) getop(i); for (int i = (1); i <= (n); i++) if (!head[i]) w[top[i]]++; dfs(1, 0); long long mx = 0; for (int i = (1); i <= (n); i++) mx = max(mx, w[i]); cout << w[1] << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int n, k, near[1010000], d[1010000], f[1010000]; vector<int> son[1010000]; int read() { int AK = 1, IOI = 0; char ch = getchar(); while (ch < '0' || ch > '9') { if (ch == '-') AK = -1; ch = getchar(); } while (ch >= '0' && ch <= '9') { IOI = (IOI << 3) + (IOI << 1) + ch - '0'; ch = getchar(); } return AK * IOI; } void build(int x, int deep) { d[x] = deep; if (!son[x].size()) { near[x] = deep; return; } near[x] = INT_MAX; for (register int i = 0; i <= son[x].size() - 1; ++i) { build(son[x][i], deep + 1); near[x] = min(near[x], near[son[x][i]]); } return; } void dp(int x) { if (!son[x].size()) { f[x] = 1; return; } f[x] = 0; for (register int i = 0; i <= son[x].size() - 1; ++i) { dp(son[x][i]); if (near[son[x][i]] - d[x] <= k) { f[x] += f[son[x][i]]; f[son[x][i]] = 0; } } return; } int answer(int x) { int Max = 0; if (son[x].size()) for (register int i = 0; i <= son[x].size() - 1; ++i) Max = max(Max, answer(son[x][i])); return f[x] + Max; } int main() { n = read(); k = read(); for (register int i = 2; i <= n; ++i) son[read()].push_back(i); build(1, 0); dp(1); cout << answer(1); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 2e6 + 10; int h[N], e[N], ne[N], idx; int f[N], g[N], len[N]; int n, k; void add(int a, int b) { e[idx] = b, ne[idx] = h[a], h[a] = idx++; } void dfs(int u, int fa) { len[u] = 0x3f3f3f3f; bool flag = true; for (int i = h[u]; ~i; i = ne[i]) { int j = e[i]; if (j == fa) continue; flag = false; dfs(j, u); len[u] = min(len[u], len[j] + 1); if (len[j] + 1 > k) g[j] = 0; g[u] += g[j]; f[u] = max(f[u], f[j] - g[j]); } if (flag) { len[u] = 0; f[u] = g[u] = 1; } else f[u] += g[u]; } int main() { memset(h, -1, sizeof h); cin >> n >> k; for (int i = 2; i <= n; i++) { int x; cin >> x; add(i, x); add(x, i); } dfs(1, -1); cout << f[1] << endl; }
#include <bits/stdc++.h> using namespace std; int n, k, d[1000005], f[1000005], p[1000005], h[1000005]; vector<int> a[1000005]; void dfs(int u) { if ((int)a[u].size() == 0) { d[u] = f[u] = 1; p[u] = h[u]; return; } int tmp = 0; p[u] = n; for (int i = 0; i < (int)a[u].size(); i++) { int v = a[u][i]; h[v] = h[u] + 1; dfs(v); if (p[v] - h[u] <= k) { p[u] = min(p[u], p[v]); d[u] += d[v]; } } for (int i = 0; i < (int)a[u].size(); i++) { int v = a[u][i]; if (p[v] - h[u] <= k) f[u] = max(f[u], d[u] - d[v] + f[v]); else f[u] = max(f[u], d[u] + f[v]); } } int main() { scanf("%d%d", &n, &k); for (int i = 2; i <= n; i++) { int x; scanf("%d", &x); a[x].push_back(i); } dfs(1); printf("%d", max(d[1], f[1])); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000050, INF = (int)1e9; const int LOG_N = 20; int root = 0; int n, m, a, b; int val[N]; vector<int> G[N]; int parent[LOG_N][N]; int dp[2][N]; int depth[N], up[N], down[N]; void dfs(int v, int p, int d) { parent[0][v] = p; depth[v] = d; for (int nxt : G[v]) { if (nxt != p) dfs(nxt, v, d + 1); } } void init(int V) { dfs(root, -1, 0); for (int k = 0; k + 1 < LOG_N; k++) { for (int v = 0; v < V; v++) { if (parent[k][v] < 0) parent[k + 1][v] = -1; else parent[k + 1][v] = parent[k][parent[k][v]]; } } } void get(int v) { dp[0][v] = val[v]; for (int nxt : G[v]) { get(nxt); dp[0][v] += dp[0][nxt]; dp[1][v] = max(dp[1][v], dp[1][nxt]); } if (up[v] == -1) { dp[1][v] = dp[1][v] + dp[0][v]; dp[0][v] = 0; } } int dfs_val(int v, int p) { if (G[v].size() == 0) { down[v] = 0; val[v] = 1; } else { down[v] = INF; for (int nxt : G[v]) { if (nxt != p) { down[v] = min(down[v], dfs_val(nxt, v) + 1); } } } int cur = v, sum = down[v]; for (int j = LOG_N - 1; j >= 0; j--) { if (parent[j][cur] != -1 && sum + (1 << j) <= m) { sum += (1 << j); cur = parent[j][cur]; } } up[v] = cur == v ? -1 : cur; return down[v]; } int main() { scanf("%d%d", &n, &m); for (int i = 1; i < n; i++) { int x; scanf("%d", &x); x--; G[x].push_back(i); } init(n); dfs_val(0, -1); get(0); cout << dp[0][0] + dp[1][0] << endl; }
#include <bits/stdc++.h> using namespace std; const int maxn = 1e6 + 5, lg = 21; vector<int> Front_Edge[maxn], Back_Edge[maxn], Component_Front[maxn]; int depth[maxn], Comp[maxn], Leaf_cnt[maxn], Comp_ASS[maxn], dp[maxn]; int par[lg][maxn]; int n, k, Comp_CNT = 1; set<pair<int, int> > Topol_set; stack<int> Rev; void Add_edge(int v, int u) { Front_Edge[v].push_back(u); Back_Edge[u].push_back(v); } void input() { cin >> n >> k; for (int i = 1; i < n; i++) { cin >> par[0][i]; par[0][i]--; Add_edge(par[0][i], i); } } void Update_parents() { for (int i = 1; i < lg; i++) for (int j = 0; j < n; j++) par[i][j] = par[i - 1][par[i - 1][j]]; } void Basic_dfs(int v) { for (auto u : Front_Edge[v]) { depth[u] = depth[v] + 1; Basic_dfs(u); } Rev.push(v); } int Get_to_height(int v, int h) { for (int i = lg - 1; i > -1; i--) if (depth[par[i][v]] >= h) v = par[i][v]; return v; } void Add_Extra_Edges() { for (int i = 1; i < n; i++) if (!Front_Edge[i].size()) Add_edge(i, Get_to_height(i, depth[i] - k)); } void DFS_Back(int v) { for (auto u : Back_Edge[v]) { if (Comp[u]) continue; Comp[u] = Comp[v]; DFS_Back(u); } } void Comp_Decomp() { while (Rev.size()) { int v = Rev.top(); Rev.pop(); if (!Comp[v]) { Comp[v] = Comp_CNT; DFS_Back(v); Comp_CNT++; } } } void Find_ans() { for (int i = 1; i < n; i++) { if (Front_Edge[i].size() == 1 and depth[Front_Edge[i][0]] < depth[i]) Leaf_cnt[Comp[i]]++; } } void Add_Comp_Edge(int c1, int c2) { Component_Front[c1].push_back(c2); Comp_ASS[c2]++; } void Making_comp_tree() { for (int i = 0; i < n; i++) for (auto u : Front_Edge[i]) if (Comp[i] != Comp[u]) Add_Comp_Edge(Comp[i], Comp[u]); } void Making_Topol_Set() { for (int i = 1; i < Comp_CNT; i++) { Topol_set.insert(make_pair(Comp_ASS[i], i)); } } void Dec(int C) { auto A = Topol_set.find(make_pair(Comp_ASS[C], C)); Topol_set.erase(A); Comp_ASS[C]--; Topol_set.insert(make_pair(Comp_ASS[C], C)); } int Updating() { int Ans = 0; while (Topol_set.size()) { pair<int, int> P = *(Topol_set.begin()); Topol_set.erase(Topol_set.begin()); int c = P.second; dp[c] = max(dp[c], Leaf_cnt[c]); Ans = max(Ans, dp[c]); for (auto C : Component_Front[c]) { Dec(C); dp[C] = max(dp[C], Leaf_cnt[C] + dp[c]); } } return Ans; } void solve() { Update_parents(); Basic_dfs(0); Add_Extra_Edges(); Comp_Decomp(); Find_ans(); Making_comp_tree(); Making_Topol_Set(); cout << Updating(); } int main() { ios::sync_with_stdio(false); cout.tie(0); cin.tie(0); input(); solve(); }
#include <bits/stdc++.h> using namespace std; int dp[2][1000005], isLeaf[1000005]; vector<int> g[1000005]; int tag[50]; int dfs(int u, int lev, int k) { if (g[u].size() == 0) { isLeaf[u] = 1; return lev; } int mn = 1000005, ret = 0; for (int i = 0; i < g[u].size(); i++) { int v = g[u][i]; mn = min(mn, dfs(v, lev + 1, k)); if (!isLeaf[v]) { dp[1][u] += dp[1][v]; ret = max(ret, dp[0][v] - dp[1][v]); } else dp[1][u] += 1; } dp[0][u] = dp[1][u] + ret; dp[1][u] = ((mn - lev) < k) * dp[1][u]; return mn; } int main() { int i, j, k, l, m, n; scanf("%d %d", &n, &k); for (i = 2; i <= n; i++) { int p; scanf("%d", &p); g[p].push_back(i); } int cnt = 1; dfs(1, 0, k); int ans = dp[0][1]; printf("%d\n", ans); return 0; }
#include <bits/stdc++.h> using namespace std; int const MAXN = 2e6 + 9; vector<int> g[MAXN]; int n, k; int dp[MAXN], minDepth[MAXN], depth[MAXN], leaf[MAXN]; void dfs(int node, int par) { if (node != par) depth[node] = 1 + depth[par]; if (node != par && g[node].size() == 1) { minDepth[node] = depth[node] - k, leaf[node]++; } int mx = 0; for (auto child : g[node]) { if (child == par) continue; dfs(child, node); if (minDepth[child] <= depth[node]) { minDepth[node] = min(minDepth[node], minDepth[child]); leaf[node] += leaf[child]; } } } void solve(int node, int par) { dp[node] = (node != par && g[node].size() == 1); for (auto child : g[node]) { if (child == par) continue; solve(child, node); int tmp = leaf[node]; if (minDepth[child] <= depth[node]) { tmp -= leaf[child]; } dp[node] = max(dp[node], tmp + dp[child]); } } int main() { ios_base::sync_with_stdio(0), cin.tie(0); cin >> n >> k; for (int u = 2; u <= n; u++) { int v; cin >> v; g[u].push_back(v); g[v].push_back(u); } for (int i = 0; i <= n + 9; i++) minDepth[i] = 1e9; dfs(1, 1); solve(1, 1); cout << dp[1]; }
#include <bits/stdc++.h> #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native") using namespace std; using ii = pair<int, int>; using ll = long long; using db = long double; using PT = pair<ll, ll>; const int N = 1e6 + 5, K = 105, MOD = 1e9 + 7; const ll MX = 1e15; bool leaf[N]; vector<int> adj[N]; int n, k; struct num { int goUp, retVal, nonRetVal; num() {} }; num dfs(int u) { num ret; if (leaf[u]) { ret.goUp = k; ret.retVal = 1; ret.nonRetVal = 1; return ret; } vector<num> canReturn; vector<num> canNotReturn; for (auto v : adj[u]) { auto x = dfs(v); x.goUp--; if (x.goUp >= 0) { canReturn.push_back(x); } else canNotReturn.push_back(x); } ret.goUp = 0; ret.retVal = 0; ret.nonRetVal = 0; for (auto x : canReturn) { ret.goUp = max(x.goUp, ret.goUp); ret.retVal += x.retVal; } ret.nonRetVal = ret.retVal; int mx = 0; for (auto x : canNotReturn) { mx = max(mx, x.nonRetVal); } ret.nonRetVal += mx; for (auto x : canReturn) { ret.nonRetVal = max(ret.nonRetVal, ret.retVal - x.retVal + x.nonRetVal); } return ret; } int main() { ios_base::sync_with_stdio(0); cin.tie(0); memset(leaf, 1, sizeof leaf); cin >> n >> k; for (int i = 2, p; i <= n; i++) { cin >> p; leaf[p] = false; adj[p].push_back(i); } auto ans = dfs(1); cout << ans.nonRetVal << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; const int MAXN = (int)1e6; vector<int> g[MAXN + 1]; pair<int, int> arr[MAXN + 1]; int k; void dfs(int nod, int par, int lvl) { arr[nod] = {2 * MAXN, 0}; for (auto it : g[nod]) { if (it != par) { dfs(it, nod, lvl + 1); if (lvl >= arr[it].first) { arr[nod].first = min(arr[nod].first, arr[it].first); arr[nod].second += arr[it].second; } } } if (g[nod].size() == 0) { arr[nod] = {lvl - k, 1}; } } int dp[MAXN + 1]; void dfs1(int nod, int par, int lvl) { dp[nod] = (g[nod].size() == 0); for (auto it : g[nod]) { if (it != par) { dfs1(it, nod, lvl + 1); int cur = arr[nod].second; if (lvl >= arr[it].first) { cur -= arr[it].second; } dp[nod] = max(dp[nod], cur + dp[it]); } } } int main() { int i, n, x, y; ios::sync_with_stdio(false); cin >> n >> k; for (i = 2; i <= n; i++) { cin >> x; g[x].push_back(i); } dfs(1, 0, 1); dfs1(1, 0, 1); cout << dp[1]; return 0; }
#include <bits/stdc++.h> #pragma GCC optimize("Ofast") #pragma GCC target("avx,avx2,fma") using namespace std; const int N = 1e6 + 7; const int INF = 1e9 + 7; pair<int, int> dp[N]; int val[N]; int p[N], h[N]; int n, k, ans; vector<int> g[N]; void calc(int v) { h[v] = h[p[v]] + 1; if (g[v].size() == 0) { dp[v].first = val[v] = 1; dp[v].second = h[v] - k; } else dp[v].second = INF; for (int to : g[v]) { calc(to); if (dp[to].second <= h[v]) dp[v].first += dp[to].first; dp[v].second = min(dp[v].second, dp[to].second); } for (int to : g[v]) { if (dp[to].second <= h[v]) val[v] = max(val[v], dp[v].first - dp[to].first + val[to]); else val[v] = max(val[v], dp[v].first + val[to]); } ans = max(ans, val[v]); } int main() { cin >> n >> k; for (int i = 2; i <= n; i++) { scanf("%d", &p[i]); g[p[i]].push_back(i); } calc(1); cout << ans; }
#include <bits/stdc++.h> #pragma GCC optimize("Ofast") using namespace std; template <typename T> void uin(T &a, T b) { if (b < a) a = b; } template <typename T> void uax(T &a, T b) { if (b > a) a = b; } const long long maxn = 1000 * 1000 + 228; long long n, k; long long dp[maxn], p[maxn]; long long dpret[maxn], hret[maxn]; vector<long long> g[maxn]; void dfs(long long v, long long deep = 0) { hret[v] = deep; if ((long long)g[v].size() == 1 && v != 1) { dp[v] = 1; dpret[v] = 1; hret[v] = max(0LL, deep - k); } else { for (long long to : g[v]) { if (to != p[v]) { dfs(to, deep + 1); if (hret[to] <= deep) { dpret[v] += dpret[to]; uin(hret[v], hret[to]); } } } dp[v] = dpret[v]; for (long long to : g[v]) { if (to != p[v]) { if (hret[to] <= deep) { uax(dp[v], dp[to] + dpret[v] - dpret[to]); } else { uax(dp[v], dp[to] + dpret[v]); } } } } } void solve() { ios_base::sync_with_stdio(false); cin.tie(0); cin >> n >> k; for (long long i = 2; i <= n; ++i) { cin >> p[i]; g[i].push_back(p[i]); g[p[i]].push_back(i); } dfs(1); cout << dp[1] << '\n'; } signed main() { ios_base::sync_with_stdio(false); cin.tie(0); solve(); return 0; }
#include <bits/stdc++.h> using namespace std; const int maxn = 1000010; const int inf = 0x3f3f3f3f; vector<int> g[maxn]; int n, k; pair<int, int> dp_ret[maxn]; int dp_to[maxn], dep[maxn], ans; void dfs(int u) { dp_ret[u] = pair<int, int>(0, inf); dp_to[u] = 0; if (g[u].size() == 0) { dp_ret[u] = pair<int, int>(1, dep[u]); dp_to[u] = 1; } for (int i = 0; i < (int)g[u].size(); i++) { int v = g[u][i]; dep[v] = dep[u] + 1; dfs(v); if (dp_ret[v].second - k <= dep[u]) { dp_ret[u].first += dp_ret[v].first; dp_ret[u].second = min(dp_ret[u].second, dp_ret[v].second); } } dp_to[u] = dp_ret[u].first; int sum = dp_ret[u].first; for (int i = 0; i < (int)g[u].size(); i++) { int v = g[u][i]; if (dp_ret[v].second - k <= dep[u]) { dp_to[u] = max(dp_to[u], sum - dp_ret[v].first + dp_to[v]); } else { dp_to[u] = max(dp_to[u], sum + dp_to[v]); } } ans = max(ans, dp_to[u]); } int main() { int p; scanf("%d%d", &n, &k); for (int i = 2; i <= n; i++) { scanf("%d", &p); g[p].push_back(i); } dfs(1); printf("%d\n", ans); return 0; }
#include <bits/stdc++.h> using namespace std; #pragma GCC optimize("Ofast") const int N = 1e6 + 10; const int INF = INT_MAX; const int MAXLOG = 20; const int MOD = 1e9 + 7; int n, k, par[N], cnt[N], dp[N], c = 1, cmp[N]; vector<int> in[N], out[N], in1[N], out1[N], path, fn, f; bool mark[N], lf[N]; void Dfs(int v) { mark[v] = 1; if (v != 1) { int sz = path.size(); par[v] = path[max((int)path.size() - k, 0)]; } if (out[v].size() == 0) lf[v] = 1; path.push_back(v); for (auto u : out[v]) if (!mark[u]) Dfs(u); path.pop_back(); } void DFS(int v) { mark[v] = 1; for (int u : out[v]) if (!mark[u]) DFS(u); fn.push_back(v); } void SDF(int v) { cmp[v] = c; for (int u : in[v]) if (cmp[u] == 0) SDF(u); } void ftime(int v) { mark[v] = 1; for (int u : out1[v]) if (!mark[u]) ftime(u); f.push_back(v); } int main() { ios::sync_with_stdio(0), cin.tie(0), cout.tie(0); cin >> n >> k; for (int i = 2; i <= n; i++) { int x; cin >> x; in[i].push_back(x); out[x].push_back(i); } Dfs(1); for (int i = 1; i <= n; i++) if (lf[i]) in[par[i]].push_back(i), out[i].push_back(par[i]); memset(mark, 0, sizeof mark); for (int i = 1; i <= n; i++) if (!mark[i]) DFS(i); reverse(fn.begin(), fn.end()); for (int i : fn) if (!cmp[i]) SDF(i), c++; for (int i = 1; i <= n; i++) for (int j : out[i]) if (cmp[i] != cmp[j]) in1[cmp[j]].push_back(cmp[i]), out1[cmp[i]].push_back(cmp[j]); for (int i = 1; i <= n; i++) if (lf[i]) cnt[cmp[i]]++; dp[1] = cnt[1]; memset(mark, 0, sizeof mark); ftime(1); reverse(f.begin(), f.end()); for (int u : f) for (int v : out1[u]) dp[v] = max(dp[u] + cnt[v], dp[v]); cout << *max_element(dp, dp + n + 1); return 0; }
#include <bits/stdc++.h> using std::max; using std::min; using std::queue; using std::stack; const int N = 1e6 + 10; const int M = N << 2; const int LOGN = 22; void file(const char *str) { char in[100], out[100]; sprintf(in, "%s.in", str), sprintf(out, "%s.out", str); freopen(in, "r", stdin), freopen(out, "w", stdout); } const int _IB = 1e6; char _ibuf[_IB], *_s, *_t; long long read() { long long a = 0; int op = 1; char ch = (_s == _t && (_t = (_s = _ibuf) + fread(_ibuf, 1, _IB, stdin), _s == _t) ? EOF : *_s++); while (ch < '0' || '9' < ch) { if (ch == '-') op = -1; ch = (_s == _t && (_t = (_s = _ibuf) + fread(_ibuf, 1, _IB, stdin), _s == _t) ? EOF : *_s++); } while ('0' <= ch && ch <= '9') { a = (a << 3) + (a << 1) + (48 ^ ch); ch = (_s == _t && (_t = (_s = _ibuf) + fread(_ibuf, 1, _IB, stdin), _s == _t) ? EOF : *_s++); } return a * op; } struct L { int to, next; }; struct Graph { L l[M]; int head[N]; int lcount; } g[2]; void add(Graph &g, int from, int to) { g.l[++g.lcount].to = to; g.l[g.lcount].next = g.head[from]; g.head[from] = g.lcount; } int n, k; int f[N][LOGN]; long long value[N]; int low[N]; int dfn[N]; int dfn_count; int color[N]; int color_count; int sum[N]; long long dp[N]; long long ans; stack<int> s; bool is_in[N]; int in[N]; void build(int now = 1) { for (int i = 1; i < LOGN; i++) f[now][i] = f[f[now][i - 1]][i - 1]; for (int i = g[0].head[now], to; to = g[0].l[i].to, i; i = g[0].l[i].next) { f[to][0] = now; build(to); } if (!g[0].head[now]) { value[now] = 1; int x = now; for (int i = 0; i < LOGN; i++) if (k & (1 << i)) x = f[x][i]; add(g[0], now, max(1, x)); } } void dfs(int now) { is_in[now] = 1; low[now] = dfn[now] = ++dfn_count; s.push(now); for (int i = g[0].head[now], to; to = g[0].l[i].to, i; i = g[0].l[i].next) { if (!dfn[to]) { dfs(to); low[now] = min(low[now], low[to]); } else if (is_in[to]) { low[now] = min(low[now], dfn[to]); } } if (dfn[now] == low[now]) { ++color_count; while (1) { is_in[s.top()] = 0; color[s.top()] = color_count; if (s.top() == now) { s.pop(); break; } s.pop(); } } } void make() { for (int i = 1; i <= n; i++) { sum[color[i]] += value[i]; for (int j = g[0].head[i], to; to = g[0].l[j].to, j; j = g[0].l[j].next) { if (color[i] != color[to]) { add(g[1], color[i], color[to]); in[color[to]]++; } } } } void DAG() { queue<int> q; for (int i = 1; i <= color_count; i++) { if (!in[i]) { dp[i] = sum[i]; q.push(i); } } int now; while (!q.empty()) { now = q.front(); q.pop(); for (int i = g[1].head[now], to; to = g[1].l[i].to, i; i = g[1].l[i].next) { in[to]--; if (!in[to]) { q.push(to); } dp[to] = max(dp[to], dp[now] + sum[to]); } } } void input() { n = read(); k = read(); for (int i = 2; i <= n; i++) add(g[0], read(), i); } void ini() {} void solve() { build(); dfs(1); make(); DAG(); for (int i = 1; i <= color_count; i++) ans = max(ans, dp[i]); } void output() { printf("%lld\n", ans); } void test() { input(); ini(); solve(); output(); } void all() { file("J"); test(); } int main() { test(); return 0; }
#include <bits/stdc++.h> using namespace std; void solve() { int n, k; cin >> n >> k; vector<bool> leaf(n, true), pa(n, -1); vector<vector<int>> g(n); for (int i = 1; i < n; i++) { int x; cin >> x; x--; pa[i] = x; leaf[x] = false; g[x].push_back(i); } vector<int> once(n), many(n); vector<int> arm(n); function<void(int)> dfs = [&](int u) { if (leaf[u]) { once[u] = many[u] = 1; return; } arm[u] = 1e8; int delta = 0; for (int v : g[u]) { dfs(v); arm[u] = min(arm[u], arm[v] + 1); many[u] += many[v]; delta = max(delta, once[v] - many[v]); } once[u] = many[u] + delta; if (arm[u] >= k) many[u] = 0; }; dfs(0); cout << once[0]; } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); solve(); return 0; }
#include <bits/stdc++.h> using namespace std; int inf = 1000000007; int k; int dp[1000000 + 50]; vector<int> adj[1000000 + 50]; int h[1000000 + 50]; pair<int, int> p[1000000 + 50]; void hei(int v, int par, int curh) { h[v] = curh; for (auto bc : adj[v]) { if (bc == par) continue; hei(bc, v, curh + 1); } } void pre(int v, int par) { p[v] = make_pair(inf, 0); for (auto bc : adj[v]) { if (bc == par) continue; h[bc] = h[v] + 1; pre(bc, v); if (p[bc].first <= h[v]) { p[v].second += p[bc].second; p[v].first = min(p[v].first, p[bc].first); } } if (adj[v].size() == 1 && v != 1) { p[v] = make_pair(h[v] - k, 1); } } void calc(int v, int par) { dp[v] = (v >= 1 && adj[v].size() == 1); for (auto bc : adj[v]) { if (bc == par) continue; calc(bc, v); int tmp = p[v].second; if (p[bc].first <= h[v]) tmp -= p[bc].second; dp[v] = max(dp[v], tmp + dp[bc]); } } int main() { ios::sync_with_stdio(false); int n, x; cin >> n >> k; for (int i = 2; i <= n; i++) { cin >> x; adj[i].push_back(x); adj[x].push_back(i); } pre(1, 0); calc(1, 0); cout << dp[1]; }
#include <bits/stdc++.h> using namespace std; const int maxn = 1e6 + 10; const int inf = 0x3f3f3f3f; struct Edge { int to, nxt; } E[maxn << 1]; int n, k; int head[maxn], cnt; void addedge(int u, int v) { E[++cnt].to = v; E[cnt].nxt = head[u]; head[u] = cnt; } int dp[maxn]; int step[maxn]; int siz[maxn]; void dfs(int u, int fa) { step[u] = inf; for (int i = head[u]; i; i = E[i].nxt) { int v = E[i].to; if (v == fa) continue; dfs(v, u); siz[u] += siz[v]; step[u] = min(step[u], step[v] + 1); dp[u] = max(dp[u], dp[v] - siz[v]); } dp[u] += siz[u]; if (step[u] == inf) dp[u] = siz[u] = 1, step[u] = 0; if (step[u] >= k) siz[u] = 0; } int main() { scanf("%d%d", &n, &k); for (int p, i = 2; i <= n; i++) { scanf("%d", &p); addedge(p, i); } dfs(1, 0); printf("%d", dp[1]); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000006; int n, k, p[N]; vector<int> g[N]; int st[N], pt; int cnt[N]; int prec(int u) { st[pt++] = u; int ans = N - 1; for (int v : g[u]) ans = min(ans, prec(v)); if (g[u].empty()) { cnt[st[max(0, pt - k - 1)]]++; st[pt--] = N - 1; return max(0, pt - k); } if (ans < pt - 1) { cnt[st[ans]] += cnt[u]; cnt[u] = 0; } st[pt--] = N - 1; return ans; } int f(int u) { int ans = 0; for (int v : g[u]) ans = max(ans, f(v)); return ans + cnt[u]; } int main() { scanf("%d %d", &n, &k); for (int i = 2; i <= n; i++) { scanf("%d", p + i); g[p[i]].push_back(i); } prec(1); printf("%d\n", f(1)); }
#include <bits/stdc++.h> using namespace std; const int maxn = 1e6 + 10; const int mod = 1e9 + 7; const long long inf = 1e18; int n, K; vector<int> gg[maxn]; int a[maxn], c[maxn]; int par[maxn][20], h[maxn]; vector<int> g[maxn], g1[maxn], bg[maxn]; int com[maxn]; void dfs_par(int v) { for (int i = 1; (1 << i) <= h[v]; i++) par[v][i] = par[par[v][i - 1]][i - 1]; for (auto u : gg[v]) if (u != par[v][0]) { par[u][0] = v; h[u] = h[v] + 1; g[v].push_back(u); bg[u].push_back(v); dfs_par(u); } } int get_par(int v, int he) { he = min(he, h[v]); int i = 0; while (he) { if (he & 1) v = par[v][i]; i++; he >>= 1; } return v; } vector<int> ord; bool mark[maxn]; void dfs(int v) { mark[v] = 1; for (auto u : g[v]) if (!mark[u]) dfs(u); ord.push_back(v); } void bdfs(int v, int k) { mark[v] = 1; com[v] = k; for (auto u : bg[v]) if (!mark[u]) bdfs(u, k); } void dfs_topol(int v) { mark[v] = 1; for (auto u : g1[v]) if (!mark[u]) dfs_topol(u); ord.push_back(v); } int mx[maxn]; void get_scc() { for (int v = 1; v <= n; v++) if (!mark[v]) dfs(v); memset(mark, 0, sizeof mark); int k = 0; while (ord.size()) { int v = ord.back(); ord.pop_back(); if (!mark[v]) { k++; bdfs(v, k); } } memset(mark, 0, sizeof mark); for (int v = 1; v <= n; v++) { for (auto u : g[v]) if (com[v] != com[u]) g1[com[v]].push_back(com[u]); c[com[v]] += a[v]; } for (int v = 1; v <= k; v++) if (!mark[v]) dfs_topol(v); int ans = 0; for (auto v : ord) { mx[v] = c[v]; for (auto u : g1[v]) mx[v] = max(mx[v], mx[u] + c[v]); } cout << mx[com[1]]; } signed main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin >> n >> K; for (int u = 2; u <= n; u++) { int v; cin >> v; gg[u].push_back(v); gg[v].push_back(u); } dfs_par(1); for (int v = 1; v <= n; v++) { if (gg[v].size() != 1) continue; if (v != 1) a[v] = 1; int u = get_par(v, K); g[v].push_back(u); bg[u].push_back(v); } get_scc(); }
#include <bits/stdc++.h> using namespace std; const int N = 1e6 + 1; int h[N], f[N], g[N], cnt, n, m, dep[N], dp[N]; struct nod { int nxt, to; } e[N]; inline bool isdigit(const char &ch) { return (ch >= '0' && ch <= '9'); } inline int read() { register int s = 0; register bool m = false; register char ch = getchar(); while (!isdigit(ch)) { if (ch == '-') m = true; ch = getchar(); } while (isdigit(ch)) s = (s << 1) + (s << 3) + (ch ^ 48), ch = getchar(); return m ? -s : s; } inline void add(const int &u, const int &v) { e[++cnt] = (nod){h[u], v}; h[u] = cnt; } inline void _SOL(const int &u, const int &fa) { dep[u] = dep[fa] + 1; if (!h[u]) { g[u] = dep[u]; f[u] = 1; return; } for (register int i = h[u]; i; i = e[i].nxt) { register int v = e[i].to; _SOL(v, u); if (!g[u]) g[u] = g[v]; else g[u] = min(g[v], g[u]); if (g[v] - dep[u] <= m) f[u] += f[v]; } } inline void __SOL(const int &u) { dp[u] = f[u]; for (register int i = h[u]; i; i = e[i].nxt) { register int v = e[i].to; __SOL(v); dp[u] = max(dp[u], dp[v] + f[u] - (g[v] - dep[u] <= m ? f[v] : 0)); } } signed main(int _lzh, char const *__lzh[]) { n = read(), m = read(); for (register int i = 2; i <= n; ++i) add(read(), i); _SOL(1, 0); __SOL(1); printf("%d\n", dp[1]); return 0; }
#include <bits/stdc++.h> using namespace std; inline long long read() { long long x = 0; char ch = getchar(); bool f = 0; for (; !isdigit(ch); ch = getchar()) if (ch == '-') f = 1; for (; isdigit(ch); ch = getchar()) x = x * 10 + ch - '0'; return f ? -x : x; } void write(long long x) { if (x < 0) putchar('-'), x = -x; if (x >= 10) write(x / 10); putchar(x % 10 + '0'); } void writeln(long long x) { write(x); puts(""); } void writep(long long x) { write(x); putchar(' '); } long long const N = 1e6 + 3; long long const inf = 1e9; long long n, k, cnt, ans, vis[N], h[N], dep[N], sz[N], mn[N]; struct edge { long long nt, to; } e[N]; void add(long long x, long long y) { e[++cnt] = (edge){h[x], y}; h[x] = cnt; } void dfs1(long long x, long long d) { dep[x] = d; mn[x] = inf; if (!vis[x]) mn[x] = d; for (long long i = h[x]; i; i = e[i].nt) { long long v = e[i].to; dfs1(v, d + 1); mn[x] = min(mn[x], mn[v]); } } void dfs2(long long x) { if (!vis[x]) sz[x] = 1; for (long long i = h[x]; i; i = e[i].nt) { long long v = e[i].to; dfs2(v); if (mn[v] - dep[x] <= k) { sz[x] += sz[v]; sz[v] = 0; } } } long long dfs(long long x) { long long res = 0; for (long long i = h[x]; i; i = e[i].nt) { long long v = e[i].to; res = max(res, dfs(v)); } return res + sz[x]; } signed main() { n = read(); k = read(); for (long long i = 2; i <= n; i++) { long long x = read(); add(x, i); vis[x] = 1; } dfs1(1, 0); dfs2(1); writeln(dfs(1)); return 0; }
#include <bits/stdc++.h> using namespace std; template <class I> inline void ckMax(I& p, I q) { p = (p > q ? p : q); } template <class I> inline void ckMin(I& p, I q) { p = (p < q ? p : q); } template <class I> inline I Min(I p, I q) { return p < q ? p : q; } template <class I> inline I Max(I p, I q) { return p > q ? p : q; } template <class I> inline void sp(I& p, I& q) { I x = p; p = q, q = x; } const int N = 1000005; int n, h[N], nxt[N], adj[N], t, k, fa[N], f[N], g[N], a[N], d[N]; inline void add(const int u, const int v) { nxt[++t] = h[u], h[u] = t, adj[t] = v; }; inline void dfs(const int x) { if (!h[x]) return f[x] = a[x] = 1, d[x] = 0, void(); d[x] = 1e9; for (register int i = h[x], j; i; i = nxt[i]) dfs(j = adj[i]), ckMin(d[x], d[j] + 1), ckMax(f[x], f[j] - a[j]), a[x] += a[j]; f[x] += a[x]; if (d[x] >= k) a[x] = 0; } int main() { scanf("%d%d", &n, &k); register int i; for (i = 2; i <= n; ++i) scanf("%d", &fa[i]), add(fa[i], i); dfs(1), printf("%d", f[1]); return 0; }
#include <bits/stdc++.h> using namespace std; long long int cons; long long int check(long long int a) { if (a >= cons) a %= cons; return a; } long long int check2(long long int a) { a %= cons; if (a < 0) a += cons; return a; } long long int fast_check(long long int a) { if (a >= cons) a -= cons; return a; } long long int GCD(long long int a, long long int b) { while (a && b) { a = a % b; if (a != 0) b = b % a; } return a + b; } long long int exp(long long int a, long long int n) { long long int ans = 1; a = check(a); while (n) { if (n & 1) ans = check(ans * a); a = check(a * a); n = (n >> 1); } return ans; } void print_pair(pair<int, int> p) { cout << p.first << " " << p.second << endl; } long long int nc2(long long int a) { return (a * (a - 1)) / 2; } const int N = 1e6 + 10; int pa[21][N]; int direct[N]; int accu[N]; int sink[N]; int k, n; bool isparent[N]; vector<int> graph[N]; int leaf[N]; int lift(int i, int k) { for (int j = 20; j >= 0; j--) { if ((1 << j) <= k && pa[j][i]) { i = pa[j][i]; k -= (1 << j); } } assert(i > 0); return i; } void leafy(int i) { leaf[i] = 1e9; for (auto itr : graph[i]) { leafy(itr); leaf[i] = min(leaf[i], leaf[itr] + 1); } if (leaf[i] == 1e9) leaf[i] = 0; } void dfs(int i) { for (auto itr : graph[i]) { dfs(itr); if (leaf[itr] < k) { accu[i] += accu[itr]; sink[i] = max(sink[i], sink[itr] - accu[itr]); } else sink[i] = max(sink[i], sink[itr]); } accu[i] += direct[i]; sink[i] += accu[i]; } int main() { ios::sync_with_stdio(false); cin.tie(0); cons = 1e9 + 7; srand(time(NULL)); cin >> n >> k; for (int i = 2; i <= n; i++) { cin >> pa[0][i]; isparent[pa[0][i]] = true; graph[pa[0][i]].push_back(i); } for (int i = 1; i <= 20; i++) for (int j = 1; j <= n; j++) pa[i][j] = pa[i - 1][pa[i - 1][j]]; for (int i = n; i >= 1; i--) if (!isparent[i]) direct[lift(i, k)]++; leafy(1); dfs(1); cout << max(accu[1], sink[1]); return 0; }
#include <bits/stdc++.h> using namespace std; vector<int> t[1000000]; int dp[1000000]; int up[1000000]; int val[1000000]; int n, k; void dfs(int cur, int h) { for (int i = 0; i < t[cur].size(); i++) dfs(t[cur][i], h + 1); if (t[cur].size() == 0) { up[cur] = max(0, h - k); val[cur] = 1; dp[cur] = 1; } else { int all = 0; up[cur] = h; for (int i = 0; i < t[cur].size(); i++) { up[cur] = min(up[cur], up[t[cur][i]]); if (up[t[cur][i]] <= h) val[cur] += val[t[cur][i]]; } for (int i = 0; i < t[cur].size(); i++) { int mm = 0; if (up[t[cur][i]] <= h) mm = val[t[cur][i]]; dp[cur] = max(dp[cur], val[cur] - mm + dp[t[cur][i]]); } } } int main() { scanf("%d %d", &n, &k); for (int i = 0; i < n; i++) up[i] = 2000000000; for (int i = 0; i < n - 1; i++) { int tmp; scanf("%d", &tmp); t[tmp - 1].push_back(i + 1); } dfs(0, 0); printf("%d\n", dp[0]); return 0; }
#include <bits/stdc++.h> using namespace std; const long long inf = 9.2e18; const int maxn = 1e6 + 70; const int INF = 2.1e9; const int maxm = 1e6 + 70; const int MOD = 1e9 + 7; const double eps = 1e-7; const double PI = acos(-1.0); int n, m, k; int fa[maxn], anc[maxn][26], dep[maxn], mind[maxn], top[maxn], cnt[maxn]; vector<int> G[maxn]; void dfs(int u) { if (!G[u].size()) mind[u] = dep[u]; else { mind[u] = INF; for (int i = 0; i < G[u].size(); i++) { int v = G[u][i]; dep[v] = dep[u] + 1; dfs(v); mind[u] = min(mind[u], mind[v]); } } } void dfs2(int u) { if (!G[u].size()) { int fk; if (dep[u] <= k) fk = 1; else { fk = u; int c = 0, t = k; while (t) { if (t & 1) fk = anc[fk][c]; t >>= 1; c++; } } top[u] = top[fk]; cnt[top[u]]++; } else { if (mind[u] - k >= dep[u]) top[u] = u; else { int fk, t = k - mind[u] + dep[u]; if (dep[u] <= t) fk = 1; else { fk = u; int c = 0; while (t) { if (t & 1) fk = anc[fk][c]; t >>= 1; c++; } } top[u] = top[fk]; } for (int i = 0; i < G[u].size(); i++) { int v = G[u][i]; dfs2(v); } } } int solve(int u) { int ans = 0; for (int i = 0; i < G[u].size(); i++) { int v = G[u][i]; ans = max(ans, solve(v)); } ans += cnt[u]; return ans; } void bfs() { queue<int> Q; Q.push(1); int now = 0; while (!Q.empty()) { int u = Q.front(); Q.pop(); if (dep[u] > now) { cout << endl; now = dep[u]; } cout << u << " "; for (int i = 0; i < G[u].size(); i++) { int v = G[u][i]; Q.push(v); } } cout << endl; } int main() { while (cin >> n >> k) { for (int i = 0; i <= n; i++) G[i].clear(); fa[1] = -1; for (int i = 2; i <= n; i++) { scanf("%d", &fa[i]); G[fa[i]].push_back(i); } dep[1] = 0; dfs(1); for (int i = 1; i <= n; i++) { anc[i][0] = fa[i]; for (int j = 1; (1 << j) < n; j++) anc[i][j] = -1; } for (int j = 1; (1 << j) < n; j++) { for (int i = 1; i <= n; i++) { if (anc[i][j - 1] != -1) { anc[i][j] = anc[anc[i][j - 1]][j - 1]; } } } memset(cnt, 0, (n + 1) * sizeof(int)); top[1] = 1; dfs2(1); int ans = solve(1); printf("%d\n", ans); } return 0; }
#include <bits/stdc++.h> using namespace std; long long n, p, dp[1000005], deep[1000005], leaf[1000005], k; vector<long long> a[1000005]; void dfs(long long u) { if (a[u].size() == 0) { deep[u] = 0; leaf[u] = 1; dp[u] = 1; return; } deep[u] = 1e9; for (long long j = (0); j <= (a[u].size() - 1); ++j) { long long v = a[u][j]; dfs(v); if (deep[v] < k) leaf[u] += leaf[v]; deep[u] = min(deep[u], deep[v] + 1); } for (long long j = (0); j <= (a[u].size() - 1); ++j) { long long v = a[u][j], tmp = dp[v]; if (deep[v] < k) tmp -= leaf[v]; dp[u] = max(dp[u], tmp + leaf[u]); } } int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin >> n >> k; for (long long i = (2); i <= (n); ++i) { cin >> p; a[p].push_back(i); } dfs(1); cout << dp[1]; }
#include <bits/stdc++.h> using namespace std; const int MAXN = 1e6; int n, k, tot, head[MAXN + 5], f[MAXN + 5], g[MAXN + 5], closest[MAXN + 5]; bool vis[MAXN + 5]; struct Edge { int next, to; } e[MAXN + 5]; inline void addEdge(int u, int v) { e[++tot] = (Edge){head[u], v}; head[u] = tot; } void dfs(int u) { if (!vis[u]) { f[u] = g[u] = 1; return; } closest[u] = n; for (int v, i = head[u]; v = e[i].to, i; i = e[i].next) { dfs(v); closest[u] = min(closest[u], closest[v] + 1); if (closest[v] + 1 > k) g[v] = 0; g[u] += g[v]; f[u] = max(f[u], f[v] - g[v]); } f[u] += g[u]; } int main() { ios::sync_with_stdio(0); cin.tie(0); cin >> n >> k; for (int x, i = 1; i < n; ++i) { cin >> x; addEdge(x, i + 1); vis[x] = 1; } dfs(1); cout << f[1] << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; const long long int maxn = (1e6) + 10, mod = 1e9 + 7; long long int n, k, lf[maxn], h[maxn], dp[maxn], pd[maxn]; vector<long long int> G[maxn], v1, v2; void pre_DFS(long long int v) { for (long long int u : G[v]) { h[u] = h[v] + 1; pre_DFS(u); } } void DFS(long long int v) { if (!G[v].size()) { lf[v] = h[v], dp[v] = pd[v] = 1; return; } else lf[v] = mod; for (long long int u : G[v]) { DFS(u); lf[v] = min(lf[v], lf[u]); } for (long long int u : G[v]) if (lf[u] - k <= h[v]) dp[v] += dp[u]; pd[v] = dp[v]; for (long long int u : G[v]) { if (lf[u] - k <= h[v]) pd[v] = max(pd[v], dp[v] + (pd[u] - dp[u])); else pd[v] = max(pd[v], dp[v] + pd[u]); } } int32_t main() { ios::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin >> n >> k; for (long long int i = 2; i <= n; i++) { long long int x; cin >> x; G[x].push_back(i); } pre_DFS(1); DFS(1); cout << pd[1] << endl; }
#include <bits/stdc++.h> using namespace std; int n, m, cnt; int head[2000005], vet[2000005], Next[2000005]; int d[2000005], f[2000005], g[2000005], len[2000005]; void add(int x, int y) { cnt++; Next[cnt] = head[x]; head[x] = cnt; vet[cnt] = y; } void dfs(int x, int fa) { d[x] = d[fa] + 1; len[x] = 0x3f3f3f3f, f[x] = 0; int tot = 0; for (int i = head[x]; i; i = Next[i]) { int v = vet[i]; if (v == fa) continue; tot++; dfs(v, x); len[x] = min(len[x], len[v]); if (len[v] - d[x] > m) g[v] = 0; f[x] = max(f[x], f[v] - g[v]); g[x] += g[v]; } if (!tot) len[x] = d[x], g[x] = f[x] = 1; else f[x] += g[x]; } int main() { cin >> n >> m; int x; for (int i = 2; i <= n; i++) { scanf("%d", &x); add(x, i); } dfs(1, 0); cout << f[1] << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int maxd = 1e9 + 7; struct node { int to, nxt; } sq[2001000]; int n, k, head[1001000], all = 0, dp[1001000], dis[1001000], back[1001000]; int read() { int x = 0, f = 1; char ch = getchar(); while ((ch < '0') || (ch > '9')) { if (ch == '-') f = -1; ch = getchar(); } while ((ch >= '0') && (ch <= '9')) { x = x * 10 + (ch - '0'); ch = getchar(); } return x * f; } void add(int u, int v) { all++; sq[all].to = v; sq[all].nxt = head[u]; head[u] = all; } void dfs(int u, int fa) { dis[u] = maxd; int i; for (i = head[u]; i; i = sq[i].nxt) { int v = sq[i].to; if (v == fa) continue; dfs(v, u); dis[u] = min(dis[u], dis[v] + 1); back[u] += back[v]; dp[u] = max(dp[u], dp[v] - back[v]); } dp[u] += back[u]; if (dis[u] == maxd) { dis[u] = 0; dp[u] = back[u] = 1; } if (dis[u] >= k) back[u] = 0; } int main() { n = read(); k = read(); int i; for (i = 2; i <= n; i++) { int v = read(); add(i, v); add(v, i); } memset(dp, 0, sizeof(dp)); memset(dis, 0, sizeof(dis)); memset(back, 0, sizeof(back)); dfs(1, 0); printf("%d", dp[1]); return 0; }
#include <bits/stdc++.h> using namespace std; inline long long read() { long long x = 0, f = 1; char c = getchar(); while (c < '0' || c > '9') { if (c == '-') f = -1; c = getchar(); } while (c >= '0' && c <= '9') { x = (x << 1) + (x << 3) + c - '0'; c = getchar(); } return x * f; } int n, k, a[1000100], dp[1000100], up[1000100], dep[1000100], f[1000100]; int st[1000100], top; vector<int> G[1000100], leaf; void dfs0(int u) { for (auto v : G[u]) { dep[v] = dep[u] + 1; f[v] = u; dfs0(v); } } void dfs1(int u) { if (G[u].empty()) { a[u] = 1; --a[up[u]]; } for (auto v : G[u]) { dfs1(v); a[u] += a[v]; } --top; } void dfs2(int u) { if (G[u].empty()) { dp[u] = 1; return; } int sum = 0; for (auto v : G[u]) { dfs2(v); sum += a[v]; } for (auto v : G[u]) { dp[u] = max(dp[u], sum - a[v] + dp[v]); } } int main() { n = read(), k = read(); for (int i = 2; i <= n; ++i) { int fa = read(); G[fa].push_back(i); } dfs0(1); for (int i = 1; i <= n; ++i) { if (G[i].empty()) leaf.push_back(i); } sort(leaf.begin(), leaf.end(), [&](int i, int j) { return dep[i] < dep[j]; }); memset(up, 255, sizeof(up)); up[0] = 0; for (auto x : leaf) { int u = x, tmp = 0; for (int i = 1; i <= k; ++i) { u = f[u]; tmp = u; if (~up[u]) { tmp = up[u]; break; } } up[x] = tmp; u = x; for (int i = 1; i <= k; ++i) { u = f[u]; if (~up[u]) break; up[u] = tmp; } } dfs1(1); dfs2(1); printf("%d\n", dp[1]); return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000100; const int M = 20; vector<int> g[N]; vector<int> gr[N]; vector<int> ord; int sp[N][M]; int tin[N]; int tout[N]; int timer; void pre_dfs(int v, int p = -1) { sp[v][0] = (p == -1 ? v : p); for (int i = 1; i < M; i++) { sp[v][i] = sp[sp[v][i - 1]][i - 1]; } tin[v] = timer++; for (int to : g[v]) { pre_dfs(to, v); } tout[v] = timer++; } inline bool anc(int u, int v) { return (tin[u] <= tin[v] && tout[u] >= tout[v]); } int get_par(int v, int k) { for (int i = 0; i < M; i++) { if ((k >> i) & 1) { v = sp[v][i]; } } return v; } bool mark[N]; void dfs1(int v) { mark[v] = 1; for (int to : g[v]) { if (!mark[to]) { dfs1(to); } } ord.push_back(v); } bool good[N]; int comp[N]; int val[N]; int cur; void dfs2(int v) { comp[v] = cur; val[cur] += good[v]; for (int to : gr[v]) { if (comp[to] == -1) { dfs2(to); } } } int dp[N]; int dfs_end(int v) { if (dp[v] != -1) return dp[v]; dp[v] = val[v]; for (int to : g[v]) { dp[v] = max(dp[v], dfs_end(to) + val[v]); } return dp[v]; } int main() { ios::sync_with_stdio(false); cin.tie(0); int n, k; cin >> n >> k; vector<pair<int, int>> ed; for (int i = 1; i < n; i++) { int p; cin >> p; --p; g[p].push_back(i); gr[i].push_back(p); ed.emplace_back(p, i); } pre_dfs(0); for (int i = 0; i < n; i++) { good[i] = g[i].empty(); if (!good[i]) continue; int up = get_par(i, k); g[i].push_back(up); gr[up].push_back(i); } for (int i = 0; i < n; i++) { if (!mark[i]) { dfs1(i); } } memset(comp, -1, sizeof(comp)); for (int i = n - 1; i >= 0; i--) { int v = ord[i]; if (comp[v] == -1) { dfs2(v); ++cur; } } for (int i = 0; i < n; i++) { g[i].clear(); gr[i].clear(); } for (auto u : ed) { int x = comp[u.first]; int y = comp[u.second]; if (x != y) { g[x].push_back(y); } } memset(dp, -1, sizeof(dp)); cout << dfs_end(comp[0]) << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const int MOD = 998244353; const int N = 2e6 + 6; int n, k; vector<int> g[N]; int h[N]; vector<pair<int, int> > c[N]; inline void merge(int v, int to) { pair<int, int> mx1 = {1e9, 0}, mx2 = {1e9, 0}; for (auto &x : c[v]) { if (x.first - h[v] <= k) { mx1.first = min(mx1.first, x.first); mx1.second += x.second; } else { if (x.second > mx2.second) mx2 = x; } } int vg = 0, vh = 1e9; for (auto &x : c[to]) { if (x.first - h[v] <= k) { mx1.first = min(mx1.first, x.first); mx1.second += x.second; } else { vg += x.second; vh = x.first; if (x.second > mx2.second) mx2 = x; } } if (vg > mx2.second) mx2 = {vh, vg}; c[v].clear(); c[v].push_back(mx1); c[v].push_back(mx2); } inline void dfs(int v) { if (g[v].size() == 0) { c[v].push_back({h[v], 1}); } for (int to : g[v]) { h[to] = h[v] + 1; dfs(to); merge(v, to); } } int main() { ios::sync_with_stdio(0); cin.tie(0); cin >> n >> k; for (int i = 2; i <= n; ++i) { int x; cin >> x; g[x].push_back(i); } dfs(1); int ans = 0; for (auto &x : c[1]) ans += x.second; cout << ans; }
#include <bits/stdc++.h> using namespace std; int n, k, d[1000006]; pair<int, int> dp[1000006]; vector<int> g[1000006]; void dfs(int v) { dp[v].first = 1000000007ll; if (g[v].size() == 0) { dp[v] = make_pair(0, 1); d[v] = 1; } else { for (int i = 0; i < g[v].size(); i++) { int to = g[v][i]; dfs(to); if (dp[to].first + 1 <= k) { dp[v].second += dp[to].second; dp[v].first = min(dp[v].first, 1 + dp[to].first); } } d[v] = dp[v].second; for (int i = 0; i < g[v].size(); i++) if (dp[g[v][i]].first + 1 <= k) d[v] = max(d[v], dp[v].second - dp[g[v][i]].second + d[g[v][i]]); else d[v] = max(d[v], dp[v].second + d[g[v][i]]); } } int main() { cin >> n >> k; for (int i = 1; i <= n - 1; i++) { int to; scanf(" %d", &to); g[to].push_back(i + 1); } dfs(1); cout << d[1] << endl; return 0; }
#include <bits/stdc++.h> using namespace std; template <class T> inline bool read(T &x) { x = 0; bool f = 0; char ch; for (ch = getchar(); !isdigit(ch); ch = getchar()) { if (ch == EOF) return 0; f |= ch == '-'; } for (; isdigit(ch); ch = getchar()) x = (x << 1) + (x << 3) + (ch ^ 48); if (f) x = -x; return 1; } template <class T> void write(T x) { if (x < 0) { putchar('-'); write(-x); return; } if (x > 9) write(x / 10); putchar(x % 10 | 48); } template <class T> inline void writeln(T x) { write(x); putchar('\n'); } template <class T> inline void writespace(T x) { write(x); putchar(' '); } const string taskname = "zero"; long long n, k; long long dep[1000010], fa[1000010], f[1000010], g[1000010]; long long low[1000010]; long long tot, h[1000010], ver[1000010], nxt[1000010]; bool leaf[1000010]; inline void add(long long u, long long v) { ++tot; ver[tot] = v; leaf[u] = 0; nxt[tot] = h[u]; h[u] = tot; } void dfs(long long u) { dep[u] = dep[fa[u]] + 1; if (leaf[u]) g[u] = 1, low[u] = dep[u]; else low[u] = 1e9; for (register long long i = h[u]; i; i = nxt[i]) { long long v = ver[i]; dfs(v); low[u] = min(low[v], low[u]); } for (register long long i = h[u]; i; i = nxt[i]) { long long v = ver[i]; if (low[v] - dep[u] <= k) g[u] += g[v], g[v] = 0; } } void dp(long long u) { for (register long long i = h[u]; i; i = nxt[i]) { long long v = ver[i]; dp(v); f[u] = max(f[u], f[v]); } f[u] += g[u]; } signed main() { srand(20050210); read(n); read(k); for (register long long i = 1; i <= n; ++i) leaf[i] = 1; for (register long long i = 2; i <= n; ++i) { read(fa[i]); add(fa[i], i); } dfs(1); dp(1); write(f[1]); return 0; }
#include <bits/stdc++.h> using namespace std; int n, k; int p[1000001]; vector<int> c[1000001]; int dep[1000001]; int dep2cnt[1000001 + 1000001]; int depkleafcnt[1000001]; int depgekleafcnt[1000001]; int cntleaf[1000001]; int dp0[1000001]; int dp1[1000001]; void dfs(int u, int d) { dep[u] = d; if (c[u].empty()) { dep2cnt[d]++; cntleaf[u] = 1; } int tmp = dep2cnt[d + k]; for (int v : c[u]) { dfs(v, d + 1); depgekleafcnt[u] += depgekleafcnt[v]; cntleaf[u] += cntleaf[v]; } depkleafcnt[u] = dep2cnt[d + k] - tmp; depgekleafcnt[u] += depkleafcnt[u]; } void work(int u) { for (int v : c[u]) { work(v); } if (c[u].empty()) { dp0[u] = dp1[u] = 1; return; } if (cntleaf[u] == depgekleafcnt[u]) { dp0[u] = 0; } else { for (int v : c[u]) { dp0[u] += dp0[v]; } } for (int v : c[u]) { if (cntleaf[v] > depgekleafcnt[v]) { dp1[u] += dp0[v]; } } int delta = 0; for (int v : c[u]) { delta = max(delta, dp1[v] - dp0[v]); } dp1[u] += delta; } int main() { cin.tie(0); ios_base::sync_with_stdio(0); cin >> n >> k; for (int i = 2; i <= n; i++) { cin >> p[i]; c[p[i]].push_back(i); } dfs(1, 0); work(1); cout << dp1[1] << endl; return 0; }
#include <bits/stdc++.h> using namespace std; void INIT() { ios ::sync_with_stdio(false); } const int N = 1001000; int n, k; vector<int> g[N]; int dep[N], ans[N], mndep[N], dp[N]; void dfs1(int u, int pre) { for (auto v : g[u]) { if (v == pre) continue; dep[v] = dep[u] + 1; dfs1(v, u); } if (g[u].size() == 1 && u != 1) { mndep[u] = dep[u]; ans[u] = 1; return; } for (auto v : g[u]) { if (v == pre) continue; if (!mndep[u]) mndep[u] = mndep[v]; else mndep[u] = min(mndep[u], mndep[v]); if (mndep[v] - dep[u] <= k) ans[u] += ans[v], ans[v] = 0; } } void dfs2(int u, int pre) { for (auto v : g[u]) { if (v == pre) continue; dfs2(v, u); dp[u] = max(dp[u], dp[v]); } dp[u] += ans[u]; } int main() { INIT(); cin >> n >> k; for (register int i = 2; i <= n; i++) { int u; cin >> u; g[u].push_back(i), g[i].push_back(u); } dfs1(1, 0), dfs2(1, 0); cout << dp[1] << endl; return 0; }
#include <bits/stdc++.h> using namespace std; int n, k; std::vector<int> G[1000005]; int dp[1000005]; int dep[1000005]; int low[1000005]; int ans[1000005]; void dfs1(int v, int p) { dep[v] = dep[p] + 1; if (G[v].empty()) { low[v] = dep[v]; dp[v] = 1; } else { int h = 0x3f3f3f3f; int val = 0; for (int u : G[v]) { dfs1(u, v); if (low[u] - dep[v] <= k) { val += dp[u]; h = min(h, low[u]); } } dp[v] = val; low[v] = h; } } void dfs(int v) { ans[v] = dp[v]; for (int u : G[v]) { dfs(u); int tmp = dp[v]; if (low[u] - dep[v] <= k) tmp -= dp[u]; ans[v] = max(ans[v], tmp + ans[u]); } } int main(int argc, char const *argv[]) { ios_base::sync_with_stdio(0); cin.tie(0); cin >> n >> k; for (int i = 2; i <= n; ++i) { int p; cin >> p; G[p].push_back(i); } dep[0] = 0; dfs1(1, 0); dfs(1); std::cout << ans[1] << '\n'; return 0; }
#include <bits/stdc++.h> using namespace std; const int N = 1000000 + 5; int n, k; vector<int> g[N]; int prt[N], dwn[N], shl[N]; void dfs(int u, int dp) { if (g[u].empty()) { shl[u] = dp; prt[u] = 1; } else { shl[u] = N; for (int v : g[u]) { dfs(v, dp + 1); shl[u] = min(shl[u], shl[v]); if (shl[v] - dp <= k) { prt[u] += prt[v]; dwn[u] = max(dwn[u], dwn[v] - prt[v]); } else { dwn[u] = max(dwn[u], dwn[v]); } } } dwn[u] += prt[u]; } int main() { scanf("%d %d", &n, &k); for (int i = 2; i <= n; i++) { int p; scanf("%d", &p); g[p].push_back(i); } dfs(1, 0); printf("%d\n", dwn[1]); return 0; }
#include <bits/stdc++.h> using namespace std; int n, k; vector<int> edge[1000000 + 10]; int deep[1000000 + 10], dp[1000000 + 10], low[1000000 + 10]; int res = 0; void dfs(int rt, int first) { deep[rt] = deep[first] + 1; if (edge[rt].size() == 1 && rt != 1) { low[rt] = deep[rt]; dp[rt] = 1; return; } int minn = 1e9; for (auto i : edge[rt]) { if (i == first) continue; dfs(i, rt); if (deep[rt] + k >= low[i]) { minn = min(minn, low[i]); dp[rt] += dp[i]; } } low[rt] = minn; } void dfs1(int rt, int first, int ans) { res = max(res, ans); for (auto i : edge[rt]) { if (i == first) continue; if (deep[rt] + k >= low[i]) { dfs1(i, rt, ans); } else { dfs1(i, rt, ans + dp[i]); } } } int main() { ios::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin >> n >> k; for (int i = (2); i < (n + 1); i++) { int x; cin >> x; edge[i].push_back(x); edge[x].push_back(i); } dfs(1, 0); dfs1(1, 0, dp[1]); cout << res << "\n"; return 0; }
#include <bits/stdc++.h> using namespace std; #pragma warning(disable : 4996) const int N = 1e6 + 6; vector<int> v[N]; int mn[N], ct[N], mx[N]; int n, k; void dfs(int node, int h) { if (v[node].empty()) { ct[node] = 1; mn[node] = h - k; mx[node] = 1; return; } int x = N, y = 0; for (int to : v[node]) { dfs(to, h + 1); x = min(x, mn[to]); y += ct[to]; } for (int to : v[node]) { mx[node] = max(mx[node], y - ct[to] + mx[to]); } if (h - 1 >= x) ct[node] = y; mn[node] = x; } int main() { scanf("%d%d", &n, &k); for (int i = 1; i < n; i++) { int p; scanf("%d", &p); v[p - 1].push_back(i); } dfs(0, 0); printf("%d", mx[0]); return 0; }
#include <bits/stdc++.h> using namespace std; inline void read(int &x) { char ch; bool flag = false; for (ch = getchar(); !isdigit(ch); ch = getchar()) if (ch == '-') flag = true; for (x = 0; isdigit(ch); x = x * 10 + ch - '0', ch = getchar()) ; x = flag ? -x : x; } inline void write(int x) { static const int maxlen = 100; static char s[maxlen]; if (x < 0) { putchar('-'); x = -x; } if (!x) { putchar('0'); return; } int len = 0; for (; x; x /= 10) s[len++] = x % 10 + '0'; for (int i = len - 1; i >= 0; --i) putchar(s[i]); } const int MAXN = 1e6 + 100; int n, lim; int fa[MAXN]; vector<int> son[MAXN]; int deep[MAXN]; int MAX[MAXN]; int siz[MAXN][2]; void get_deep(int x) { if (son[x].size() == 0) { MAX[x] = x; siz[x][1] = 1; siz[x][0] = 0; } else { siz[x][0] = 0; siz[x][1] = 0; MAX[x] = 0; } for (int i = 0; i < son[x].size(); i++) { int y = son[x][i]; deep[y] = deep[x] + 1; get_deep(y); if ((MAX[x] == 0) || (deep[MAX[y]] < deep[MAX[x]])) MAX[x] = MAX[y]; if (deep[MAX[y]] <= deep[x] + lim) { siz[x][1] += siz[y][1]; siz[x][0] = max(siz[x][0], siz[y][0] - siz[y][1]); } else siz[x][0] = max(siz[x][0], siz[y][0]); } siz[x][0] += siz[x][1]; } int main() { read(n); read(lim); for (int i = 2; i <= n; i++) { read(fa[i]); son[fa[i]].push_back(i); } get_deep(1); int ans = 0; for (int i = 1; i <= n; i++) ans = max(ans, siz[i][0]); cout << ans << endl; return 0; }
#include <bits/stdc++.h> using namespace std; const long long inf = 9.2e18; const int maxn = 1e6 + 70; const int INF = 2.1e9; const int maxm = 1e6 + 70; const int MOD = 1e9 + 7; const double eps = 1e-7; const double PI = acos(-1.0); int n, m, k; vector<int> G[maxn]; int dep[maxn], mind[maxn], dp[maxn]; int dfs(int u) { if (!G[u].size()) { mind[u] = dep[u] - k; dp[u] = 1; return 1; } else { int mx = 0; mind[u] = dep[u]; dp[u] = 0; for (int i = 0; i < G[u].size(); i++) { int v = G[u][i]; dep[v] = dep[u] + 1; int val = dfs(v); mind[u] = min(mind[u], mind[v]); if (mind[v] <= dep[u]) { dp[u] += dp[v]; mx = max(mx, val - dp[v]); } else { mx = max(mx, val); } } return dp[u] + mx; } } int main() { while (cin >> n >> k) { for (int i = 1; i <= n; i++) G[i].clear(); for (int i = 2; i <= n; i++) { int f; scanf("%d", &f); G[f].push_back(i); } dep[1] = 0; int ans = dfs(1); cout << ans << endl; } return 0; }
#include <bits/stdc++.h> using namespace std; template <typename T> void out(T x) { cout << x << endl; exit(0); } const int maxn = 1e6 + 5; vector<int> g[maxn]; int n, k; int nfree[maxn]; int npay[maxn]; int depth[maxn]; void dfs(int at) { if (g[at].empty()) { depth[at] = 0; nfree[at] = 1; npay[at] = 0; return; } depth[at] = 1e9; int finale = 0; int tot = 0; for (int to : g[at]) { dfs(to); depth[at] = min(depth[at], 1 + depth[to]); finale = max(finale, npay[to]); tot += nfree[to]; } npay[at] = finale; if (depth[at] < k) { nfree[at] += tot; } else { npay[at] += tot; } } int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); cin >> n >> k; for (int i = 1; i < n; i++) { int p; cin >> p; --p; g[p].push_back(i); } dfs(0); cout << nfree[0] + npay[0] << endl; return 0; }