#include <bits/stdc++.h>

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

int log(int x) {
    int ans = 0;

    while ((1 << ans) < x) {
        ans++;
    }

    return ans;
}

void dfs(int node, int last) {
    td[node] = ++t;
    up[node][0] = last;
    for (int i = 1; i <= hmax; i++)
        up[node][i] = up[up[node][i - 1]][i - 1];

    for (auto it : v[node])
        if (it != last) {
            dfs(it, node);
        }

    tf[node] = ++t;
}

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

int lca(int x, int y) {
    if (isAncestor(x, y))
        return x;
    if (isAncestor(y, x))
        return y;
    for (int i = hmax; i >= 0; i--) {
        if (!isAncestor(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;
        v[x].push_back(i);
    }

    hmax = log(n);
    dfs(1, 1);

    while (m--) {
        in >> x >> y;
        out << lca(x, y) << '\n';
    }
    return 0;
}