小H和游戏

#pragma GCC optimize(3,"Ofast","inline")//O3优化
#pragma GCC optimize(2)//O2优化
#include <algorithm>
#include <string>
#include <cstring>
#include <vector>
#include <map>
#include <stack>
#include <set>
#include <queue>
#include <cmath>
#include <cstdio>
#include <iomanip>
#include <ctime>
#include <bitset>
#include <cmath>
#include <sstream>
#include <iostream>

#define LL long long
#define ls nod<<1
#define rs (nod<<1)+1
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
#define INF 0x3f3f3f3f
#define max(a,b) (a>b?a:b)
#define min(a,b) (a<b?a:b)

const double eps = 1e-10;
const int maxn = 8e5 + 10;
const int mod = 10;

int sgn(double a){return a < -eps ? -1 : a < eps ? 0 : 1;}
using namespace std;

vector<int> G[maxn];
int fa[maxn];
int f[maxn][3];

void dfs(int x) {
    for (int i = 0;i < G[x].size();i++) {
        int v = G[x][i];
        if (v == x || v == fa[x])
            continue;
        fa[v] = x;
        dfs(v);
    }
}

LL cal(int x) {
    LL sum = f[x][0] + f[x][1] + f[x][2];  // 孩子的影响
    if (fa[x]) { 
        sum = sum + f[fa[x]][2]; // 父亲自身的影响 
        sum = sum + f[fa[x]][1] - f[x][2]; // 兄弟的影响
    }
    if (fa[fa[x]]) {  // 父亲的父亲的影响
        sum = sum + f[fa[fa[x]]][2];
    }
    return sum;
}

int main() {
    ios::sync_with_stdio(false);
    int n,q;
    cin >> n >> q;
    for (int i = 1;i < n;i++) {
        int u,v;
        cin >> u >> v;
        G[u].push_back(v);
        G[v].push_back(u);
    }
    dfs(1);
    while (q--) {
        int x;
        cin >> x;
        f[x][2]++;
        if (fa[x]) {
            f[fa[x]][1]++;
        }
        if (fa[fa[x]])
            f[fa[fa[x]]][0]++;
        cout << cal(x) << endl;
    }
    return 0;
}