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

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

const int NMAX = 1e5+1;
const int LOGMAX = 21;
int rmq[2*NMAX][LOGMAX], euler[2*NMAX], pos[NMAX], nivel[2*NMAX], cnt;
vector<int> v[NMAX];

void parcurgere(int x, int nivelCurent) {
    euler[cnt] = x;
    nivel[cnt] = nivelCurent;
    pos[x] = cnt;
    cnt++;
    for (int i = 0; i < v[x].size(); i++) {
        parcurgere(v[x][i], nivelCurent + 1);
        euler[cnt] = x;
        nivel[cnt] = nivelCurent;
        cnt++;
    }
}

void preprocesare(int nivel[], int n) {
    for (int i = 0; i < n; i++) {
        rmq[i][0] = i;
    }
    for (int j = 1; j <= log2(n); j++) {
        for (int i = 0; i < n; i++) {
            if (i + (1 << j) <= n) {
                if (nivel[rmq[i][j-1]] < nivel[rmq[i+(1<<(j-1))][j-1]]) {
                    rmq[i][j] = rmq[i][j-1];
                } else {
                    rmq[i][j] = rmq[i+(1<<(j-1))][j-1];
                }
            }
        }
    }
}

int interogare(int st, int dr) {
    if (st  > dr) {
        swap(st, dr);
    }
    int putere = log2(dr-st+1);
    if (nivel[rmq[st][putere]] < nivel[rmq[dr-(1<<putere)+1][putere]]) {
        return euler[rmq[st][putere]];
    } else {
        return euler[rmq[dr-(1<<putere)+1][putere]];
    }
}

int main() {
    int n, m;
    in >> n >> m;
    for (int i = 2; i <= n; i++) {
        int x;
        in >> x;
        v[x].push_back(i);
    }
    parcurgere(1, 0);
    preprocesare(nivel, cnt);
    for (int i = 0; i < m; i++) {
        int x, y;
        in >> x >> y;
        out << interogare(pos[x], pos[y]) << '\n';
    }
    return 0;
}