#include <bits/stdc++.h>
#pragma GCC optimize("O3")
using namespace std;
const int MOD = 1e9 + 7;
const long long INF = 1e18;
const int nx[4] = {0, 0, 1, -1}, ny[4] = {1, -1, 0, 0};
void IO() {}
const int MX = 1e5 + 10;
int N, Q;
int c[MX];
vector<int> adj[MX];
int cnt[MX];
int szz[MX], order[MX];
int counter = 0;
vector<int> a;
int L[MX], R[MX];
vector<int> bit(MX, 0);
bool mo(pair<pair<int, int>, int> a, pair<pair<int, int>, int> b) {
  const int S = ceil(sqrt(N));
  if (a.first.first / S != b.first.first / S)
    return a.first.first / S < b.first.first / S;
  return a.first.first / S & 1 ? a.first.second < b.first.second
                               : a.first.second > b.first.second;
}
int lsb(int i) { return i & -i; }
void update(int idx, int v) {
  if (idx <= 0) return;
  while (idx < MX) {
    bit[idx] += v;
    idx += lsb(idx);
  }
}
int getSum(int idx) {
  int ans = 0;
  while (idx > 0) {
    ans += bit[idx];
    idx -= lsb(idx);
  }
  return ans;
}
void add(int x) {
  x = c[x];
  update(cnt[x], -1);
  cnt[x]++;
  update(cnt[x], 1);
}
void remove(int x) {
  x = c[x];
  update(cnt[x], -1);
  cnt[x]--;
  update(cnt[x], 1);
}
void dfs(int u, int p) {
  order[u] = counter++;
  a.push_back(u);
  szz[u] = 1;
  for (auto v : adj[u])
    if (v != p) dfs(v, u), szz[u] += szz[v];
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  IO();
  memset(cnt, 0, MX);
  cin >> N >> Q;
  for (int i = 1; i <= N; i++) cin >> c[i];
  for (int i = 0; i < N - 1; i++) {
    int u, v;
    cin >> u >> v;
    adj[v].push_back(u);
    adj[u].push_back(v);
  }
  dfs(1, 1);
  int val[Q];
  vector<pair<pair<int, int>, int>> q;
  for (int i = 0; i < Q; i++) {
    int v, x;
    cin >> v >> x;
    val[i] = x;
    q.push_back({{order[v], order[v] + szz[v] - 1}, i});
  }
  sort(begin(q), end(q), mo);
  int res[Q];
  int cl = 0, cr = -1;
  for (auto x : q) {
    int l = x.first.first, r = x.first.second, idx = x.second, xx = val[idx];
    while (cl < l) {
      remove(a[cl]);
      cl++;
    }
    while (cl > l) {
      cl--;
      add(a[cl]);
    }
    while (cr < r) {
      cr++;
      add(a[cr]);
    }
    while (cr > r) {
      remove(a[cr]);
      cr--;
    }
    res[idx] = getSum(MX - 1) - getSum(xx - 1);
  }
  for (int i = 0; i < Q; i++) cout << res[i] << "\n";
  return 0;
}
