#include <fstream>
#include <vector>
using namespace std;

ifstream fin("lca.in");
ofstream fout("lca.out");

int rmq[20][200010], log[200010], n, m, first[100005];
vector<int> g[100005], euler, nivel;

void citire() {
    fin >> n >> m;
    for(int i = 2; i <= n; i++) {
        int x;
        fin >> x;
        g[x].push_back(i);
    }
}

void dfs(int x, int t, int niv) {
    euler.push_back(x);
    nivel.push_back(niv);
    first[x] = euler.size()-1;
    for(auto next: g[x])
        if(next != t) {
            dfs(next, x, niv+1);
            euler.push_back(x);
            nivel.push_back(niv);
        }
}

void RMQ() {
    int k = euler.size();
    for(int i = 2; i <= k; i++)
        log[i] = log[i/2]+1;
    for(int i = 1; i <= k; i++)
        rmq[0][i] = i;

    for(int i = 1; (1<<i) <= k; i++)
        for(int j = 1; j+(1<<i) <= k; j++) {
            rmq[i][j] = rmq[i-1][j];
            if(nivel[rmq[i][j]] > nivel[rmq[i-1][j+(1<<(i-1))]])
                rmq[i][j] = rmq[i-1][j+(1<<(i-1))];
        }

}

int lca(int x, int y) {
    int a = min(first[x], first[y]);
    int b = max(first[x], first[y]);

    int dif = b-a+1;
    int lg = log[dif];

    int res = rmq[lg][a];
    if(nivel[res] > nivel[rmq[lg][b-(1<<lg)+1]])
        res = rmq[lg][b-(1<<lg)+1];

    return euler[res];
}

void solve() {
    dfs(1, 0, 1);
    RMQ();
    while(m--) {
        int x, y;
        fin >> x >> y;
        fout << lca(x, y) << '\n';
    }
}

int main() {
    citire();
    solve();
}