#include <fstream>
#include <cmath>
#include <vector>

#define MAXN 100005

using namespace std;

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

vector <int> graph[MAXN];

int pre[MAXN], pre2[MAXN], n, m, niv[MAXN];
int rad;

inline void DFS(int nod, int tata) {
    if (niv[nod] % rad == 1)
        tata = nod;
    else {
        pre2[nod] = tata;
    }

    for (auto x : graph[nod]) {
        niv[x] = niv[nod] + 1;
        DFS(x, tata);
    }
}

inline int LCA(int x, int y) {
    int a = niv[x];
    int b = niv[y];

    if (x == pre[y])
        return x;
    if (y == pre[x])
        return y;

    while (a > b) {
        if (pre2[x] != 0) {
            x = pre2[x];
        }
        else {
            x = pre[x];
        }
        a = niv[x];
    }

    while (b > a) {
        if (pre2[y] != 0) {
            y = pre2[y];
        }
        else {
            y = pre[y];
        }
        b = niv[y];
    }

    while (pre[x] != pre[y]) {
        x = pre[x];
        y = pre[y];
    }

    return pre[x];
}

inline void Read() {
    fin >> n >> m;

    rad = sqrt((float)n);

    int t = 0, x, y;

    for (int i = 2; i <= n; i++) {
        fin >> x;

        pre[i] = x;

        graph[x].push_back(i);
    }

    niv[1] = 1;

    DFS(1, 0);

    /*for (int i = 1; i <= n; i++) {
        fout << niv[i] << " ";
    }
    fout << "\n"; */

    for (int i = 1; i <= m; i++) {
        fin >> x >> y;

        fout << LCA(x, y) << "\n";
    }
}

int main () {
    Read();

    fin.close(); fout.close(); return 0;
}