#include<bits/stdc++.h>
#define N 100001
using namespace std;
ifstream in("lca.in");
ofstream out("lca.out");
vector<int> a[N];
int d[N], dp[N][18];
void dfs(int i){
    for(auto it:a[i]){
        if(!d[it]){
            d[it]=d[i]+1;
            dp[it][0]=i;
            dfs(it);
        }
    }
}
int main(){
    int n,m,i,h,j,x,y,z;
    in>>n>>m;
    h=log(n);
    for(i=1; i<n; ++i){
        in>>x;
        a[x].push_back(i+1);
    }
    dfs(1);
    for(i=1; i<=h; ++i)
        for(j=1; j<=n; ++j)
            dp[j][i]=dp[dp[j][i-1]][i-1];
    while(m--){
        in>>x>>y;
        if(d[x]>d[y]) swap(x,y);
        z=d[y]-d[x];
        for(i=h; i>=0 && z; --i){
            if(z-(1<<i)>=0){
                z-=(1<<i);
                y=dp[y][i];
            }
        }
        if(x==y){
            out<<x<<"\n";
            continue;
        }
        for(i=h; i>=0; --i){
            if(dp[x][i]!=dp[y][i]){
                x=dp[x][i];
                y=dp[y][i];
            }
        }
        out<<dp[x][0]<<"\n";
    }
	return 0;
}