#include <fstream>
#include <vector>

using namespace std;

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

const int nmax=100000, nmax2=16;

int f[nmax2+1][nmax+1], l[nmax+1];

vector <int> g[nmax+1];

void dfs(int x){
    for(int i=0;i<int(g[x].size());i++){
        int xn=g[x][i];
        l[xn]=l[x]+1;
        dfs(xn);
    }
}

int main(){
    int n,m;
    fin>>n>>m;
    for(int i=2;i<=n;i++){
        fin>>f[0][i];
        g[f[0][i]].push_back(i);
    }
    l[1]=1;
    dfs(1);
    for(int i=1;i<=nmax2;i++){
        for(int j=1;j<=n;j++){
            f[i][j]=f[i-1][f[i-1][j]];
        }
    }
    for(int i=1;i<=m;i++){
        int x,y;
        fin>>x>>y;
        if(l[x]<l[y]){
            int aux=x;
            x=y;
            y=aux;
        }
        for(int i=nmax2;i>=0;i--){
            if(l[x]-(1<<i)>=l[y]){
                x=f[i][x];
            }
        }
        if(x!=y){
            for(int i=nmax2;i>=0;i--){
                if(l[x]-(1<<i)>0&&f[i][x]!=f[i][y]){
                    x=f[i][x];
                    y=f[i][y];
                }
            }
            fout<<f[0][x]<<"\n";
        }else{
            fout<<x<<"\n";
        }
    }
    return 0;
}