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

const int N = 100010;
int n, m, dp[18][N], lvl[N];
vector <int> v[N];

void dfs(int q, int t){
    lvl[q] = t;
    for (auto it: v[q])
        if (!lvl[it]) dfs(it, t + 1);
}

int main(){
    ifstream cin ("lca.in");
    ofstream cout ("lca.out");
    cin >> n >> m;
    for (int i=2; i<=n; i++) cin >> dp[0][i], v[dp[0][i]].push_back(i);
    dfs(1, 1);
    for (int i=1; (1<<i)<=n; i++){
        for (int j = 1; j<=n; j++)
            dp[i][j] = dp[i-1][dp[i-1][j]];
    }
    while (m--){
        int x, y;
        cin >> x >> y;
        if (lvl[y] > lvl[x]) swap(x, y);
        while (lvl[x] > lvl[y]){
            int put = 0;
            while (lvl[dp[put+1][x]] > lvl[y]) put++;
            x = dp[put][x];
        }
        while (x != y){
            int put = 0;
            while (dp[put+1][x] != dp[put+1][y]) put++;
            x = dp[put][x]; y = dp[put][y];
        }
        cout << x << "\n";
    }
    return 0;
}