#include <fstream>
#include <vector>
#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];
vector <int> v[DIM];
int Rmq[30][DIM];

void dfs(int x,int niv){
    H[++K] = x;
    L[K] = niv;
    First[x] = K;
    for(int i=0;i<v[x].size();i++){
        dfs(v[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(){
    fin >> N >> M;
    for(int i=2;i<=N;i++){
        int x;
        fin >> x;
        v[x].push_back(i);
    }
    dfs(1,0);
    RMQ();
    while(M--){
        int x,y;
        fin >> x >> y;
        fout << lca(x, y) << "\n";
    }
    fin.close();fout.close();
    return 0;
}