#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], depth[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, int parent)
{
    up[0][node] = parent;
    depth[node] = depth[parent] + 1;
    for(int child : adj[node])
        if(child != parent)
            dfs(child, node);
}

int lca(int u, int v)
{
    if(depth[u] < depth[v])
        swap(u, v);
    for(int k = LOG - 1; k >= 0; k--)
        if(depth[up[k][u]] >= depth[v])
            u = up[k][u];
    if(u == v)
        return u;
    for(int k = LOG - 1; k >= 0; k--)
    {
        if(up[k][u] != up[k][v])
        {
            u = up[k][u];
            v = up[k][v];
        }
    }
    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, 0);
    build();
    while(q--)
    {
        int u, v;
        fin >> u >> v;
        fout << lca(u, v) << "\n";
    }

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