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

ifstream f("lca.in");
ofstream g("lca.out");

vector < int > v[100005];
int n,q;
int x,y;
int nodes[200005],depths[200005];
int aa;
bool viz[100005];
int last[100005];
pair < int , int > rmq[200005][20];

pair < int , int > minim(pair < int , int > a, pair < int , int > b) {
    if (a.first<b.first) return a;
    return b;
}

void read() {
    f >> n >> q;
    for (int i=2;i<=n;i++) {
        f >> x;
        v[x].push_back(i);
        v[i].push_back(x);
    }
}

void dfs(int nod, int depth) {
    viz[nod] = 1;
    nodes[++aa] = nod; depths[aa] = depth; last[nod] = aa;
    for (auto k:v[nod]) {
        if (!viz[k]) {
            dfs(k,depth+1);
            nodes[++aa] = nod; depths[aa] = depth; last[nod] = aa;
        }
    }
}

void create_rmq(){
    for (int i=1;i<=aa;i++) {
        rmq[i][0].first = depths[i];
        rmq[i][0].second = i;
    }
    for (int p=1;p<=18;p++) {
        for (int i=1;i<=aa-(1<<p);i++) {
            rmq[i][p] = minim(rmq[i][p-1],rmq[i+(1<<(p-1))][p-1]);
        }
    }
}

int ancestor(int a, int b) {
    int dif = b-a+1;
    int k=0;
    while ((1<<k)<=dif) k++;
    k--;
    pair < int , int > p = minim(rmq[a][k],rmq[b-(1<<k)+1][k]);
    return nodes[p.second];
}

void solve() {
    dfs(1,0);
    create_rmq();
    for (int i=1;i<=q;i++) {
        f >> x >> y;
        g << ancestor(min(last[x],last[y]),max(last[x],last[y])) << '\n';
    }
}

int main()
{
    read();
    solve();
    return 0;
}