#include <fstream>
#include <vector>
#define nmax (int)(1e5+1)
using namespace std;
ifstream cin("lca.in");
ofstream cout("lca.out");
int n,m,x,y,k,st[nmax],dr[nmax],rmq[17][nmax];
vector<int>v[nmax];
void dfs(int nod,int t){
    st[nod]=++k;
    rmq[0][nod]=t;
    for(auto i:v[nod])
        dfs(i,nod);
    dr[nod]=++k;
}
bool dad(int x,int y){
    return st[x]<=st[y]&&dr[y]<=dr[x];
}
int lca(int x,int y){
    if(dad(x,y))
        return x;
    if(dad(y,x))
        return y;
    for(int i=17;i>=0;i--){
        int z=rmq[i][x];
        if(z!=0&&!dad(z,y))
            x=z;
    }
    return rmq[0][x];
}
int main()
{
    cin>>n>>m;
    for(int i=2;i<=n;i++){
        cin>>x;
        v[x].push_back(i);
    }
    dfs(1,0);
    dr[0]=++k;
    for(int i=1;(1<<i)<=n;i++)
        for(int j=1;j<=n;j++)
            rmq[i][j]=rmq[i-1][rmq[i-1][j]];
    while(m--){
        cin>>x>>y;
        cout<<lca(x,y)<<'\n';
    }
    return 0;
}