#include <bits/stdc++.h>

using namespace std;

const int N = 1e5;

int n, m, lev[N + 2];
int tata[19][N + 2];
vector<int>fii[N + 2];

void dfs(int nod, int par) {
    for(auto iter: fii[nod]) {
       if(iter != par) {
          lev[iter] = lev[nod] + 1;
          dfs(iter, nod);
       }
    }
}

int lca(int x, int y) {
    if(lev[x] < lev[y]) swap(x, y);
    for(int pas = 17; pas >= 0; --pas)
       if(lev[x] - (1 << pas) >= lev[y]) x = tata[pas][x];
    if(x == y) return x;
    for(int pas = 17; pas >= 0; --pas)
       if(tata[pas][x] != tata[pas][y])
          x = tata[pas][x],  y = tata[pas][y];
    return tata[0][x];
}

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

    f >> n >> m;
    for(int i = 2, par; i <= n; ++i) {
       f >> par;
       tata[0][i] = par;
       fii[par].push_back(i);
    }

    dfs(1, 0);
    for(int pas = 1; (1 << pas) <= n; ++pas)
        for(int i = 1; i <= n; ++i)
            tata[pas][i] = tata[pas - 1][tata[pas - 1][i]];

    for(int i = 1, x, y; i <= m; ++i) {
       f >> x >> y;
       g << lca(x, y) << '\n';
    }

    return 0;
}