#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

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

const int nmax = 100000, lgmax = 18;

vector <int> g[nmax + 5];
int tt[nmax + 5], n, m, lev[nmax + 5], log2[nmax + 5], a[lgmax][nmax + 5];

void Read(){
    fin >> n >> m;
    for (int i = 2; i <= n; i++){
        fin >> a[0][i];
        g[a[0][i]].push_back(i);
    }
}

void CalcLevel(int nod){
    lev[nod] = lev[a[0][nod]] + 1;
    for (auto i : g[nod])
        if (!lev[i])
            CalcLevel(i);
}

void Precalc(){
    CalcLevel(1);
    for (int i = 2; i <= n; i++)
        log2[i] = log2[i / 2] + 1;
    for (int j = 1; j <= n; j++)
        for (int i = 1; i <= log2[n]; i++)
            a[i][j] = a[i - 1][a[i - 1][j]];
}

int LCA(int x, int y){
    if (lev[x] > lev[y])
        swap(x, y);
    while (lev[x] != lev[y]){
        int dif = lev[y] - lev[x];
        y = a[log2[dif]][y];
    }
    if (x == y)
        return x;
    for (int i = log2[n]; i >= 0; i--)
        if (a[i][x] != a[i][y]){
            x = a[i][x];
            y = a[i][y];
        }
    return a[0][x];
}

void Print(){
    while(m--){
        int x, y;
        fin >> x >> y;
        fout << LCA(x, y) << '\n';
    }
}

int main(){
    Read();
    Precalc();
    Print();
    return 0;
}