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

using namespace std;

int N,M,K;

vector <int> G[2*DIM];

int Lg[DIM],RMQ[30][DIM],L[DIM],First[DIM],H[DIM];

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

int read(){
    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;
    First[x]=K;
    L[K]=niv;
    for(int i=0;i<G[x].size();i++){
        dfs(G[x][i],niv+1);
        H[++K]=x;
        L[K]=niv;
    }
}
void prec(){

    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(){

    read();
    dfs(1,0);
    prec();

    while(M--){
        int x,y;
        fin >> x >> y;
        fout << lca(x,y) << " " << "\n";
    }

    fin.close();fout.close();

    return 0;

}