#include <bits/stdc++.h>
#pragma GCC optimize("O3")

using namespace std;

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

const int NMAX = 1e5, LOG = 18;

int n, m, up[NMAX + 5][LOG + 5], dt[NMAX];

vector <int> g[NMAX + 5];

void dfs (int node) {
    for (auto nx : g[node]) {
        dt[nx] = dt[node] + 1;
        dfs (nx);
    }
}

int lca (int u, int v) {
    int node_to_lift = u, other_node = v;
    if (dt[u] < dt[v])
        node_to_lift = v, other_node = u;
    int diff = dt[node_to_lift] - dt[other_node];
    for (int i = 0; i < LOG; i++) {
        if (diff & (1 << i))
            node_to_lift = up[node_to_lift][i];
    }
    if (node_to_lift == other_node)
        return node_to_lift;
    for (int i = LOG; i >= 0; i--) {
        if (up[node_to_lift][i] != up[other_node][i]) {
            node_to_lift = up[node_to_lift][i];
            other_node = up[other_node][i];
        }
    }
    return up[node_to_lift][0];
}

int main() {
    //ios::sync_with_stdio(false);
    //cin.tie(nullptr);
    fin >> n >> m;
    for (int i = 2; i <= n; i++) {
        fin >> up[i][0];
        g[up[i][0]].push_back(i); // parinte -> copil
    }
    for (int j = 1; j < LOG; j++) {
        for (int i = 1; i <= n; i++)
            up[i][j] = up[up[i][j - 1]][j - 1];
    }
    dt[1] = 0;
    dfs (1);
    while (m--) {
        int u, v;
        fin >> u >> v;
        fout << lca(u, v) << "\n";
    }
    return 0;
}