#include <vector>
#include <fstream>
#define DIM 200005

using namespace std;

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

int N,K,M;
int L[DIM],H[DIM],Lg[DIM],First[DIM];
int Rmq[30][DIM];

vector <int> G[2*DIM];

void citire(){
    fin>>N>>M;
    for(int i=2;i<=N;i++){
        int x;
        fin>>x;
        G[x].push_back(i);
    }
}
void dfs(int x,int niv){
    H[++K]=x;
    L[K]=niv;
    First[x]=K;
    for(int i=0;i<G[x].size();i++){
        dfs(G[x][i],niv+1);
        H[++K]=x;
        L[K]=niv;
    }
}
void rmq(){
    for(int i=2;i<=K;i++)
        Lg[i]=Lg[i/2]+1;
    for(int i=1;i<=K;i++)
        Rmq[0][i]=i;
    for(int i=1;(1 << i) <= K;i++)
        for(int j=1;j<=K-(1<<i);j++){
            int l=1<<(i-1);
            Rmq[i][j]=Rmq[i-1][j];
            if(L[Rmq[i][j]]>L[Rmq[i-1][j+l]])
                Rmq[i][j]=Rmq[i-1][j+l];
        }
}
int lca(int x,int y){
    int sol;
    int a=First[x],b=First[y];
    if(a>b)
        swap(a,b);
    int l=Lg[b-a+1];
    sol=Rmq[l][a];
    if(L[sol]>L[Rmq[l][b-(1<<l)+1]])
        sol=Rmq[l][b-(1<<l)+1];
    return H[sol];
}
int main(){
    citire();
    dfs(1,0);
    rmq();
    while(M--){
        int x,y;
        fin>>x>>y;
        fout<<lca(x,y)<<"\n";
    }
    fin.close();fout.close();
    return 0;
}