#include <bits/stdc++.h>
using namespace std;
int nivel[100005], t[100005][25], i, n, nod, rasp, q, x, y;
vector<int>v[100005];
ifstream fin("lca.in");
ofstream fout("lca.out");
void dfs(int nod, int prec) {
    nivel[nod]=nivel[prec]+1;
    for (int i:v[nod]) {
        if (i!=prec) dfs(i, nod);
    }
}
int urca(int nod, int nr) {
    for (i=0; i<=20; i++) {
        if (nr%2==1) {
            nod=t[nod][i];
        }
        nr/=2;
        if (nr==0) break;
    }
    return nod;
}
int main()
{
    fin>>n>>q;
    for (i=2; i<=n; i++) {
        fin>>t[i][0];
        v[i].push_back(t[i][0]);
        v[t[i][0]].push_back(i);
    }
    for (i=1; i<=20; i++) {
        for (nod=1; nod<=n; nod++)
            t[nod][i]=t[t[nod][i-1]][i-1];
    }
    dfs(1, 0);
    while (q--) {
        fin>>x>>y;
        if (nivel[x]>nivel[y]) swap(x, y);
        y=urca(y, nivel[y]-nivel[x]);
        i=20;
        if (x==y) {
            rasp=x;
            i=-1;
        }
        for (; i>=0; i--) {
            int xx=t[x][i];
            int yy=t[y][i];
            if (xx==yy) {
                rasp=xx;
            }
            else {
                x=xx;
                y=yy;
            }
        }
        fout<<rasp<<'\n';
    }
    return 0;
}