#include <bits/stdc++.h>

using namespace std;
const int N = 1e5 + 5;
int n, m;
vector <int> g[N];
int p[N], d[N], sz[N], nxt[N];
void dfs1(int u = 0)
{
    sz[u] = 1; d[u] = d[p[u]] + 1;
    for(int& v : g[u]) {
        dfs1(v);
        sz[u] += sz[v];
        if(sz[v] > sz[g[u][0]]) swap(v, g[u][0]);
    }
}
void dfs2(int u = 0)
{
    for(int v : g[u]) {
        nxt[v] = (v == g[u][0] ? nxt[u] : v);
        dfs2(v);
    }
}
int lca(int u, int v)
{
    while(nxt[u] != nxt[v]) {
        if(d[nxt[u]] < d[nxt[v]]) swap(u, v);
        u = p[nxt[u]];
    }
    return (d[u] < d[v]) ? u : v;
}

int main()
{
    ifstream cin("lca.in");
    ofstream cout("lca.out");
    ios_base :: sync_with_stdio(false); cin.tie(nullptr);
    cin >> n >> m;
    for(int i = 1; i < n; i++) {
        cin >> p[i];
        p[i]--;
        g[p[i]].push_back(i);
    }
    dfs1(); dfs2();
    for(int t = 1, u, v; t <= m; t++) {
        cin >> u >> v; u--, v--;
        cout << lca(u, v)+1 << "\n";
    }
    return 0;
}