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

using namespace std;

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

#define Nmax 100005

int n, m, Lca[Nmax][20], L[Nmax];
vector<int> G[Nmax];

void dfs(int nod, int val) {
    L[nod] = val;
    for(int y : G[nod])
        dfs(y, val + 1);
}

int query(int x, int y) {
    if(L[x] < L[y])
        swap(x, y);

    int lg = 0;
    while(1 << (lg + 1) <= L[x])
        ++lg;

    for(int i = lg; i >= 0; --i)
        if(L[x] - (1 << i) >= L[y])
            x = Lca[x][i];

    if(x == y)
        return x;

    for(int i = lg; i >= 0; --i)
        if(Lca[x][i] && Lca[x][i] != Lca[y][i])
            x = Lca[x][i], y = Lca[y][i];

    return Lca[x][0];
}

int main()
{
    fin >> n >> m;
    for(int i = 2; i <= n; ++i) {
        fin >> Lca[i][0];
        G[Lca[i][0]].push_back(i);
    }
    dfs(1, 1);

    for(int j = 1; 1 << j <= n; ++j)
        for(int i = 1; i <= n; ++i)
            if(Lca[i][j - 1])
                Lca[i][j] = Lca[Lca[i][j - 1]][j - 1];

    int x, y;
    for(int i = 1; i <= m; ++i) {
        fin >> x >> y;
        fout << query(x, y) << '\n';
    }
    return 0;
}