#include <bits/stdc++.h>

using namespace std;
const int N = 1e5;
int n, m;
vector <int> g[N];
int p[N], head[N], d[N], sz[N], k, currh;
void dfs(int u)
{
    int link = 0;
    sz[u] = 1;
    d[u] = ++currh;
    for(int v : g[u]) {
        dfs(v);
        sz[u] += sz[v];
        if(sz[link] < sz[v])
            link = v;
    }
    if(!link) p[u] = ++k;
    else p[u] = p[link];
    for(int v : g[u]) if(v != link)
        head[p[v]] = u;
    --currh;
}

int lca(int u, int v)
{
    while(p[u] != p[v]) {
        if(d[head[p[u]]] < d[head[p[v]]]) swap(u, v);
        u = head[p[u]];
    }
    if(d[u] > d[v]) swap(u, v);
    return u;
}

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 = 2, p; i <= n; i++)
        cin >> p,
        g[p].push_back(i);
    sz[0] = -1;
    dfs(1);
    for(int t = 1, u, v; t <= m; t++) {
        cin >> u >> v;
        cout << lca(u, v) << "\n";
    }
    return 0;
}