#include<bits/stdc++.h>

using namespace std;
typedef int var;

#define MAXN 100005

var D[MAXN], PathP[MAXN], Heavy[MAXN], In[MAXN];
vector<var> G[MAXN];

void dfs(var node) {
    Heavy[node] = 1;
    In[node] = node;
    var best = 0;
    for(auto vec : G[node]) {
        D[vec] = D[node] + 1;
        dfs(vec);
        Heavy[node] += Heavy[vec];
        PathP[In[vec]] = node;
        if(best < Heavy[vec]) {
            best = Heavy[vec];
            In[node] = In[vec];
        }
    }
}

var lca(var a, var b) {
    while(In[a] != In[b])
        if(D[PathP[In[a]]] > D[PathP[In[b]]])
            a = PathP[In[a]];
        else
            b = PathP[In[b]];

    if(D[a] < D[b])
        return a;
    return b;
}

int main() {
    ifstream fin("lca.in");
    ofstream fout("lca.out");

    var n, m, p, a, b;
    fin>>n>>m;
    for(var i=2; i<=n; i++) {
        fin>>p;
        G[p].push_back(i);
    }

    D[1] = 1;
    dfs(1);
    PathP[In[1]] = 0;

    while(m--) {
        fin>>a>>b;
        fout<<lca(a, b)<<'\n';
    }
    return 0;
}