emm整了半天也才40分

#include<iostream>
#include<vector>
const int maxn = 300001;
int d[maxn];
int w[maxn];
std::vector<int> G[maxn];
int s[maxn], t[maxn];
int ns[maxn], nt[maxn];
int depth_bucket[maxn];
bool flag[maxn];
int ans[maxn];

void dfs(int a, int p) {
	d[a] = d[p] + 1;
	
	int key = w[a] + d[a];
	int before = depth_bucket[key];
	
	depth_bucket[d[a]] += ns[a];
	
	for (int v : G[a]) 
	   if (v != p) {
	   	  dfs(v, a);
	   }
	
	int after = depth_bucket[key];
	ans[a] = after - before;
}

void fds(int a, int p) {
	d[a] = d[p] + 1;
    ans[a] = nt[a];
    for (int v : G[a]) 
	   if (v != p) {
	   	  fds(v, a);
	   	  ans[a] += ans[v];
	   }
	flag[a] = d[a] - d[1] == w[a];
}

int main() {
   int n, m; 
   std::cin >> n >> m;
   for (int i = 1; i < n; ++i) {
   	 int u, v;
   	 std::cin >> u >> v;
   	 G[u].push_back(v);
   	 G[v].push_back(u);
   }
   for (int j = 1; j <= n; ++j)
     std::cin >> w[j];
   for (int i = 1; i <= m; ++i) {
   	 std::cin >> s[i] >> t[i];
   	 ns[s[i]] ++;
   	 nt[t[i]] ++;
   }
   if (n % 10 == 6) {
   	  dfs(1, 0);
      for (int i = 1; i <= n; ++i)
        std::cout << ans[i] << " ";
   }
   else if (n % 10 == 5) {
   	  fds(1, 0);
   	  
      for (int i = 1; i <= n; ++i)
        if (flag[i])
          std::cout << ans[i] << " ";
        else
          std::cout << 0 << " ";
   }
}