#include<fstream>
#include<vector>
using namespace std;
ifstream in("lca.in");
ofstream out("lca.out");
const int Nmax = 100001;
vector<int> G[Nmax];
int T[Nmax],sm[21][Nmax];
int L[Nmax];
int N,M;
int lca(int x,int y){
    if(L[x]>L[y]) swap(x,y);
    int h=L[y]-L[x];
    for(int k=0;(1<<k)<=h;k++) if((1<<k)&h) y=sm[k][y];
    if(x==y) return x;
    int pas=20;
    while(pas>=0){
        if(sm[pas][x]!=sm[pas][y]){
            x=sm[pas][x];
            y=sm[pas][y];
        }
        pas--;
    }
    return T[x];
}
void dfs(int x,int l){
    L[x]=l;
    sm[0][x]=T[x];
    for(int k=1;sm[k-1][x];k++) sm[k][x]=sm[k-1][sm[k-1][x]];
    for(vector<int>::iterator it=G[x].begin();it!=G[x].end();++it) if(!L[*it]) dfs(*it,l+1);
}
int main(){
    in>>N>>M;
    for(int i=2;i<=N;i++){
        in>>T[i];
        G[T[i]].push_back(i);
    }
    dfs(1,1);
    int x,y;
    while(M--){
        in>>x>>y;
        out<<lca(x,y)<<'\n';
    }
    return 0;
}