#include <fstream>
#include <set>
#include <vector>

#define DIM 100010
#define MAX_LOG 18
using namespace std;
vector<int> L[DIM];
int pozSt[DIM], pozDr[DIM], k;

void dfs(int nod) {
    pozSt[nod] = ++k;
    for (auto vec: L[nod]) {
        dfs(vec);
    }
    pozDr[nod] = ++k;
}

int n, m;
int stramos[MAX_LOG][DIM];

void calcStramosi() {
    for (int p = 1; p < MAX_LOG; p++) {
        for (int i = 1; i <= n; i++) {
            stramos[p][i] = stramos[p - 1][stramos[p - 1][i]];
        }
    }
}

bool esteStramos(int x, int y) {
    return pozSt[x] < pozSt[y] && pozDr[y] < pozDr[x];
}

int lca(int x, int y) {
    if (esteStramos(x, y)) {
        return x;
    }
    if (esteStramos(y, x)) {
        return y;
    }
    for (int p = MAX_LOG - 1; p >= 0; p--) {
        int z = stramos[p][x];
        if (z != 0 && !esteStramos(z, y)) {
            x = z;
        }
    }
    return stramos[0][x];
}

int x, y;

int main() {
    ifstream fin("lca.in");
    ofstream fout("lca.out");
    fin >> n >> m;
    for (int i = 2; i <= n; i++) {
        fin >> stramos[0][i];
        L[stramos[0][i]].push_back(i);
    }
    dfs(1);
    calcStramosi();
    for (int i = 1; i <= m; i++) {
        fin >> x >> y;
        fout << lca(x, y) << "\n";
    }
    return 0;
}