#include <bits/stdc++.h>

#define nlim 100005

using namespace std;

ifstream f("lca.in");
ofstream g("lca.out");

vector<int> v[nlim];
int n, m, a[nlim][20], l, st[nlim], dr[nlim], k;

bool anc(int x, int y) {
    return(st[x] <= st[y] && dr[x] >= dr[y]);
}

int LCA(int x, int y) {
    if (anc(x, y)) return x;
    if (anc(y, x)) return y;
    for (int i = l; i >= 0; --i)
        if (!anc(a[x][i], y)) x = a[x][i];
    return a[x][0];
}

void DFS(int x, int t) {
    st[x] = ++k;
    a[x][0] = t;
    for (int i = 1; i <= l; ++i)
        a[x][i] = a[a[x][i - 1]][i - 1];
    for (auto it : v[x])
        DFS(it, x);
    dr[x] = ++k;
}

int main()
{
    f >> n >> m;
    l = ceil(log2(n));
    for (int i = 2; i <= n; ++i) {
        int x;
        f >> x;
        v[x].push_back(i);
    }
    DFS(1, 1);
    while (m--) {
        int a, b;
        f >> a >> b;
        g << LCA(a, b) << '\n';
    }
}