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#include <fstream>
#include <vector>
using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
int parent[18][100001],intrare[100001],iesire[100001],cnt = 0;
vector <int> muchii[100001];
bool viz[100001];
void dfs(int nod){
viz[nod] = 1;
int i;
cnt++;
intrare[nod] = cnt;
for(i = 0;i < muchii[nod].size();i++){
int vecin = muchii[nod][i];
if(!viz[vecin]){
dfs(vecin);
}
}
iesire[nod] = cnt;
}
int main()
{
int n,m,i,j;
cin >> n >> m;
for(i = 2;i <= n;i++){
cin >> parent[0][i];
muchii[i].push_back(parent[0][i]);
muchii[parent[0][i]].push_back(i);
}
for(i = 1;(1 << i) <= n;i++){
for(j = 2;j <= n;j++){
parent[i][j] = parent[i-1][parent[i-1][j]];
}
}
//cout << parent[0][3] << " ";
intrare[0] = iesire[0]=-1;
dfs(1);
int a,b;
for(i = 1;i <= m;i++){
cin >> a >> b;
//int pas = 1 << 17;
int sol = 0,r = a;
int pas = 17;
while(pas >= 0){
if(parent[pas][r] >= 1 && !(intrare[parent[pas][r]] < intrare[b] && iesire[parent[pas][r]] >= iesire[b]))
r = parent[pas][r];
pas--;
}
//cout << r << " ";
cout << parent[0][r] << "\n";
}
return 0;
}