#include <iostream>
#include <fstream>
#include <vector>
#include <math.h>

using namespace std;

vector<vector<int>> c;
vector<int> level, euler, first;
vector<vector<int>> g;

int lca(int x, int y) {
    if (first[x] > first[y])
        swap(x, y);

    int r = x;
    for (int i = first[x] + 1;i <= first[y];++i)
        if (level[euler[i]] < level[r]) r = euler[i];

    return r;
}

void dfs(int u, int l) {
    level[u] = l;
    euler.push_back(u);
    first[u] = euler.size() - 1;
    for (auto v : g[u]) {
        dfs(v, l + 1);
        euler.push_back(u);
    }
}

int main() {

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

    int n, m;
    fin >> n >> m;
    g.resize(n + 1);
    level.resize(n + 1, -1);
    first.resize(n + 1, -1);

    for (int i = 2;i <= n;++i) {
        int x;
        fin >> x;
        g[x].push_back(i);
    }
    dfs(1, 1);
    while (m--) {
        int x, y;
        fin >> x >> y;
        fout << lca(x, y) << '\n';
    }

    return 0;
}