#include <fstream>
#include <vector>

using namespace std;
ifstream fin ("lca.in");
ofstream fout ("lca.out");
int n, m, T[100010], S[100010], H[100010], inaltime;

vector <int> a[100010];

void DFS ( int nod, int stramos) {

    S[nod] = stramos;
    if (H[nod] % inaltime == 0 )
        stramos = nod;

    for (unsigned i = 0; i < a[nod].size(); i++) {
        DFS ( a[nod][i], stramos);
    }
}

int lca ( int x, int y ) {
    while (S[x] != S[y]) {
        if (H[x] > H[y])
            x = S[x];
        else y = S[y];
    }

    while (x != y)
        if (H[x] > H[y])
            x = T[x];
        else y = T[y];

    return x;
}

int main()
{
    int i, x, y;
    fin >> n >> m;

    for (i = 2; i <= n; i++) {
        fin >> T[i];
        a[ T[i] ].push_back(i);
        H[i] = H[ T[i] ]+1;
        inaltime = max (inaltime, H[i]);
    }

    for (i = 1; i*i <= inaltime; i++) ;
    inaltime = i-1;

    DFS (1, 1);
    /*for (i = 1; i <= n; i++)
        fout << S[i] << " ";*/

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