#include <bits/stdc++.h>
#define MAX (int)(1e5+5)
#define RMAX 350
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
typedef pair <int, int> pairINT;

int n,q,sz;
int Depth[MAX],lg[MAX],EulerTour[MAX*2],Poz[MAX];
vector <int> Child[MAX];
pairINT rmq[RMAX][MAX*2];

void read();
void solve();
void createRMQ();
void dfs(int,int);

int main(){
    read();
    dfs(1,1);
    createRMQ();
    solve();
    return 0;
}
void solve(){
    int x,y,dist;
    pairINT it;

    while(q--){
        fin>>x>>y;
        x=Poz[x], y=Poz[y];
        if(x>y)
            swap(x,y);
        dist=y-x;

        it=min(rmq[lg[dist]][x],
               rmq[lg[dist]][y-(1<<lg[dist])+1]);

        fout<<it.second<<'\n';
    }
}
void createRMQ(){
    int i,j;
    //precalculate lg2
    for(i=2;i<=sz;++i)
        lg[i]=lg[i/2]+1;

    for(i=1;i<=sz;++i)
        rmq[0][i]=make_pair(Depth[EulerTour[i]],EulerTour[i]);

    for(i=1;i<=lg[sz];++i){
        for(j=1;j+(1<<(i-1))<=sz;++j){
            rmq[i][j]=min(rmq[i-1][j],
                          rmq[i-1][j+(1<<(i-1))]);
        }
    }
}
void dfs(int nod,int depth){
    Depth[nod]=depth;
    EulerTour[++sz]=nod;
    if(!Poz[nod])
        Poz[nod]=sz;
    for(auto it:Child[nod]){
        dfs(it,depth+1);
        EulerTour[++sz]=nod;
    }
}
void read(){
    int i,x;
    fin>>n>>q;
    for(i=2;i<=n;++i){
        fin>>x;
        Child[x].push_back(i);
    }
}