#include <bits/stdc++.h>

using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
vector <int> G[100005];
int n;
int t[100005][18];
int depth[100005];
void dfs(int r){
    for(auto x : G[r]){
        depth[x] = depth[r] + 1;
        t[x][0] = r;
        for(int i = 1; (1 << i) <= n; i++) t[x][i] = t[t[x][i - 1]][i - 1];
        dfs(x);
    }
}
int lca(int x, int y){
    if(depth[x] < depth[y]) swap(x,y);
    int d = depth[x] - depth[y];
    for(int i = 17; i >= 0; i--){
        if((1 << i) & d) x = t[x][i];
    }
    if(x == y) return x;
    for(int i = 17; i >= 0; i--){
        if(t[x][i] != t[y][i]){
            x = t[x][i];
            y = t[y][i];
        }
    }
    return t[x][0];
}
int main()
{
    int m,i,x,y;
    fin >> n >> m;
    t[1][0] = 1;
    for(i = 2; i <= n; i++){
        fin >> x;
        G[x].push_back(i);
    }
    dfs(1);
    for(i = 1; i <= m; i++){
        fin >> x >> y;
        fout << lca(x,y) << "\n";
    }
    return 0;
}