#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];

stack<var> ST;
var At[MAXN];
void dfs(var start) {
    D[0] = -1;
    ST.push(start);
    Heavy[start] = 1;
    while(!ST.empty()) {
        var node = ST.top();
        if(At[node] == G[node].size()) {
            ST.pop();
            var best = 0;
            In[node] = node;
            for(auto vec : G[node]) {
                Heavy[node] += Heavy[vec];
                PathP[In[vec]] = node;
                if(best < Heavy[vec]) {
                    best = Heavy[vec];
                    In[node] = In[vec];
                }
            }
        } else {
            var vec = G[node][At[node]];
            At[node]++;
            D[vec] = D[node] + 1;
            Heavy[vec] = 1;
            ST.push(vec);
        }
    }
    PathP[In[1]] = 0;
}

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() {
    freopen("lca.in", "r", stdin);
    freopen("lca.out", "w", stdout);

    var n, m, p, a, b;
    cin>>n>>m;
    for(var i=2; i<=n; i++) {
        cin>>p;
        G[p].push_back(i);
    }
    dfs(1);


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