#include <bits/stdc++.h>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
const int NMAX = 1e5 + 1, LOG = 19;
vector<int> adj[NMAX];
int n, q, up[LOG][NMAX], start[NMAX], finish[NMAX], timp;
bool vis[NMAX];

void build()
{
    for(int k = 1; k < LOG; k++)
        for(int node = 1; node <= n; node++)
            up[k][node] = up[k-1][up[k-1][node]];
}

void dfs(int node)
{
    start[node] = ++timp;
    vis[node] = true;
    for(int child : adj[node])
        if(!vis[child])
            dfs(child);
    finish[node] = ++timp;
}

bool ancestor(int u, int v)
{
    return (u == 0 || (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 k = LOG - 1; k >= 0; k--)
        if(!ancestor(up[k][u], v))
            u = up[k][u];
    return up[0][u];
}

int main()
{
    fin >> n >> q;
    for(int i = 2; i <= n; i++)
    {
        int parent;
        fin >> parent;
        up[0][i] = parent;
        adj[parent].push_back(i);
    }
    build();
    dfs(1);
    while(q--)
    {
        int u, v;
        fin >> u >> v;
        fout << lca(u, v) << "\n";
    }

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