#include <bits/stdc++.h>

using namespace std;

#define pb push_back
#define ll long long
#define INF 1000000000
#define MOD 666013

const int NMAX = 1e5 + 5;

int parent[NMAX], depth[NMAX], pos[NMAX], rmq[2 * NMAX][17];

vector <int> g[NMAX];
bool leaf[NMAX];
vector <int> euler;

void DFS(int node, int parent, int dep) {
    euler.pb(node);
    depth[node] = dep;
    if (pos[node] == -1) pos[node] = euler.size() - 1;
    for (int x: g[node]) {
        if (x != parent) {
            DFS(x, node, dep + 1);
            euler.pb(node);
        }
    }
}

int aux (int x, int y) {
    if (depth[x] < depth[y]) return x;
    return y;
}

int Query (int x, int y) {
    if (x > y) swap(x, y);
    int a = __lg(y - x + 1);
    return aux(rmq[x][a], rmq[y - (1 << a) + 1][a]);
}

int main() {
    ifstream cin("lca.in");
    ofstream cout("lca.out");
    ios::sync_with_stdio(false), cin.tie(0);
    int n, q;
    cin >> n >> q;
    for (int i = 2, x; i <= n; i++) {
        cin >> x;
        parent[i] = x;
        g[x].pb(i);
        g[i].pb(x);
    }

    for (int i = 1; i <= n; i++) pos[i] = -1;

    DFS(1, 0, 0);

    for (int i = 0; i < euler.size(); i++) rmq[i][0] = euler[i];

    for (int k = 1; k < 17; k++)
        for (int i = 0; i < euler.size(); i++) rmq[i][k] = aux(rmq[i][k - 1], rmq[i + (1 << (k - 1))][k - 1]);

    while (q--) {
        int x, y;
        cin >> x >> y;
        cout << Query(pos[x], pos[y]) << '\n';
    }
    return 0;
}