#include <bits/stdc++.h>
using ll=long long;
#define S second
#define F first
#define endl '\n'
#define spid ios_base::sync_with_stdio(false);cin.tie(NULL);
const int mod=1e9+7;
const double pi=3.14159265359;
const int maxn=100001;
using namespace std;

int n,m,parent[maxn],depth[maxn];
vector<vector<int>> A(maxn,vector<int>());
int dp[19][maxn];

void deepfs(int i){
	for(int j=0;j<A[i].size();j++){
		if(A[i][j]!=parent[i]){
			depth[A[i][j]]=depth[i]+1;
			deepfs(A[i][j]);
		}
	}
}

int lift(int i,int k){
	for(int j=0;j<=18;j++){
		if(k&(1<<j)){
			i=dp[j][i];
		}
	}
	return i;
}

int lca(int a,int b){
	if(depth[a]<depth[b]){
		b=lift(b,depth[b]-depth[a]);
	}
	else if(depth[b]<depth[a]){
		a=lift(a,depth[a]-depth[b]);
	}
	if(a==b)return a;
	for(int i=18;i>=0;i--){
		if(dp[i][a]!=dp[i][b]){
			a=dp[i][a];
			b=dp[i][b];
		}
	}
	return parent[a];
}

int main(){
	ifstream cin("lca.in");
	ofstream cout("lca.out");
	cin>>n>>m;
	for(int i=1;i<n;i++){
		cin>>parent[i];
		parent[i]--;
		A[i].push_back(parent[i]);
		A[parent[i]].push_back(i);
	}
	deepfs(0);
	for(int i=0;i<n;i++){
		dp[0][i]=parent[i];
	}
	for(int i=1;i<=18;i++){
		for(int j=0;j<n;j++){
			dp[i][j]=dp[i-1][dp[i-1][j]];
		}
	}
	while(m--){
		int a,b;
		cin>>a>>b;
		a--;b--;
		cout<<lca(a,b)+1<<endl;
	}
}