#include <bits/stdc++.h>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
const int NMAX = 1e5 + 1, LOG = 18;
vector<int> adj[NMAX];
int n, q, start[NMAX], finish[NMAX], up[LOG][NMAX], timp;

void dfs(int node, int parent)
{
    start[node] = ++timp;
    up[0][node] = parent;
    for(int i = 1; i < LOG; i++)
        up[i][node] = up[i - 1][up[i - 1][node]];
    for(int child : adj[node])
        if(child != parent)
            dfs(child, node);
    finish[node] = ++timp;
}

bool ancestor(int u, int v)
{
    return (start[u] <= start[v] && finish[v] <= finish[u]);
}

int lca(int u, int v)
{
    if(ancestor(u, v))
        return u;
    if(ancestor(v, u))
        return v;
    for(int i = LOG - 1; i >= 0; i--)
        if(!ancestor(up[i][u], v))
            u = up[i][u];
    return up[0][u];
}

int main()
{
    fin >> n >> q;
    for(int i = 2; i <= n; i++)
    {
        int parent;
        fin >> parent;
        adj[parent].push_back(i);
    }
    dfs(1, 1);
    while(q--)
    {
        int u, v;
        fin >> u >> v;
        fout << lca(u, v) << "\n";
    }

    fin.close();
    fout.close();
    return 0;
}