#include <bits/stdc++.h>

using namespace std;

ifstream in("lca.in");
ofstream out("lca.out");
int n,m,v[100005],v2[100005],nivel[100005];
vector<int> graf[100005];
const int HMAX=300;
void dfs(int nod,int nod1,int lvl)
{
	nivel[nod]=lvl;

	v2[nod]=nod1;
    if(lvl%HMAX==0) nod1=nod;


	for(auto x:graf[nod])
		dfs(x,nod1,lvl+1);
}
int main()
{
	int n,m;
	in>>n>>m;
	for(int i=2;i<=n;i++)
	{
		in>>v[i];
		graf[v[i]].push_back(i);
	}
	dfs(1,1,0);
	while(m--)
	{
		int x,y;
		in>>x>>y;
		while(v2[x]!=v2[y])
		{
			if(nivel[x]>nivel[y])
				x=v2[x];
			else
				y=v2[y];
		}
		while(x!=y)
		{
			if(nivel[x]>nivel[y])
				x=v[x];
			else
				y=v[y];
		}
		out<<x<<"\n";
	}
	return 0;
}