HackWA求调...

#include<bits/stdc++.h>
using namespace std;
#define int long long

const int MAX = 5e5+5;
int n, q, fa[MAX][35], dep[MAX];
vector<int> mp[MAX];

void dfs(int x, int f, int depth)
{
    dep[x] = depth;
    fa[x][0] = f;
    for(int i=1; i<=30; i++)
        fa[x][i] = fa[fa[x][i-1]][i-1];
    
    for(int i=0; i<mp[x].size(); i++)
        if(mp[x][i] != f) dfs(mp[x][i], x, depth+1);
}

int up(int x, int h)
{
    int i=0;
    while(h)
    {
        if(h & 1) x = fa[x][i];
        h >>= 1; i++;
    }
    return x;
}

int LCA(int a, int b)
{
    if(dep[a] < dep[b]) swap(a, b);
    a = up(a, dep[a]-dep[b]);
    if(a == b) return a;

    for(int i=30; i>=0; i--)
        if(fa[a][i] != fa[b][i])
            a = fa[a][i],
            b = fa[b][i];
    return fa[a][0];
}

signed main()
{
    // freopen("a.in", "r", stdin);

    cin >> n;
    for(int i=1; i<n; i++)
    {
        int f; cin >> f;
        mp[f].push_back(i);
        mp[i].push_back(f);
    }

    dfs(0, 0, 1);
    cin >> q; 
    for(int i=1; i<=q; i++)
    {
        int m, lca=0; cin >> m;
        for(int j=1; j<=m; j++)
        {
            int a; cin >> a;
            if(j == 1) lca = a;
            lca = LCA(a, lca);
        }
        cout << lca << endl;
    }

    return 0;
}