func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1e5 + 5;   const int INF = 0x3f3f3f3f;   int m, n, c[N], cnt[N];   vector<int> g[N];   int bit[N];   void add(int x, int t) {     for (; x <= n; x += x & -x) bit[x] += t;   }   int ask(int x) {     int ret = 0;     for (; x > 0; x -= x & -x) ret += bit[x];     return ret;   }   struct Que {     int p, c, ret;   } q[N];   vector<int> geet[N];   int st[N], ed[N], clk, sz[N], son[N], mat[N];   void predfs(int u, int f) {     st[u] = ++clk, mat[clk] = u, son[u] = -1, sz[u] = 1;     for (int i = 0; i < (int)g[u].size(); ++i) {       int v = g[u][i];       if (v == f) continue;       predfs(v, u);       sz[u] += sz[v];       if (son[u] == -1 || sz[v] > sz[son[u]]) son[u] = v;     }     ed[u] = clk;   }   void dfs(int u, int f, bool keep) {     for (int i = 0; i < (int)g[u].size(); ++i) {       int v = g[u][i];       if (v == f || v == son[u]) continue;       dfs(v, u, 0);     }     if (son[u] != -1) dfs(son[u], u, 1);     ++cnt[c[u]];     if (cnt[c[u]] - 1 > 0) add(cnt[c[u]] - 1, -1);     add(cnt[c[u]], 1);     for (int i = 0; i < (int)g[u].size(); ++i) {       int v = g[u][i];       if (v == f || v == son[u]) continue;       for (int j = st[v]; j <= ed[v]; ++j) {         ++cnt[c[mat[j]]];         if (cnt[c[mat[j]]] - 1 > 0) add(cnt[c[mat[j]]] - 1, -1);         add(cnt[c[mat[j]]], 1);       }     }     for (int i = 0; i < (int)geet[u].size(); ++i) {       int id = geet[u][i];       q[id].ret = ask(n) - ask(min(n, q[id].p - 1));     }     if (!keep) {       for (int i = st[u]; i <= ed[u]; ++i) {         add(cnt[c[mat[i]]], -1);         --cnt[c[mat[i]]];         if (cnt[c[mat[i]]]) add(cnt[c[mat[i]]], 1);       }     }   }   int main() {     while (~scanf( %d%d , &n, &m)) {       for (int i = 1; i <= n; ++i) {         scanf( %d , &c[i]);       }       for (int i = 0; i < N; ++i) g[i].clear(), geet[i].clear();       memset(bit, 0, sizeof(bit));       memset(cnt, 0, sizeof(cnt));       clk = 0;       for (int i = 1; i < n; ++i) {         int u, v;         scanf( %d%d , &u, &v);         g[u].push_back(v);         g[v].push_back(u);       }       predfs(1, 0);       for (int i = 1; i <= m; ++i) {         int u;         scanf( %d%d , &u, &q[i].p);         geet[u].push_back(i);       }       dfs(1, 0, 1);       for (int i = 1; i <= m; ++i) {         printf( %d n , q[i].ret);       }     }     return 0;   }   