#include <bits/stdc++.h>

using namespace std;
ifstream in("lca.in");
ofstream out("lca.out");
int n, m, td[100005], tf[100005], x, y;
vector<int> adj[100005];
int up[100005][30];
int timp = 0;
int l;

int logg(int x) {
    int ans = 0;
    while ((1 << ans) < x)
        ans++;

    return ans;
}

void dfs(int nod, int papa) {
    td[nod] = ++timp;

    up[nod][0] = papa;
    for (int i = 1; i <= l; i++)
        up[nod][i] = up[up[nod][i - 1]][i - 1];

    for (auto it : adj[nod])
        if (it != papa) {
            dfs(it, nod);
        }

    tf[nod] = ++timp;
}

bool is_ancestor(int x, int y) {
    return td[x] <= td[y] && tf[x] >= tf[y];
}

int lca(int x, int y) {
    if (is_ancestor(x, y))
        return x;
    if (is_ancestor(y, x))
        return y;

    for (int i = l; i >= 0; i--)
        if (!is_ancestor(up[x][i], y))
            x = up[x][i];

    return up[x][0];
}

int main()
{
    in >> n >> m;
    for (int i = 2; i <= n; i++) {
        in >> x;
        adj[x].push_back(i);
    }
    l = logg(n);
    dfs(1, 1);

    while (m--) {
        in >> x >> y;
        out << lca(x, y) << '\n';
    }

    return 0;
}