#include <vector>
#include <fstream>
#include <cstdlib>
#define N_MAX 100011
#define Log2N_MAX 20

using namespace std;
int Index;
int idx[N_MAX], level[N_MAX];
int RMQ[Log2N_MAX][N_MAX];
vector< int > G[N_MAX];
inline void GetEulerTur( int x, int lev )
{
	level[x]=lev;
	RMQ[0][++Index]=x;
	idx[x]=( idx[x] <= Index ? idx[x] : Index ); 
	if( G[x].empty() )
		return;
	vector< int >::const_iterator it=G[x].begin(), iend=G[x].end();
	for( ; it < iend; ++it )
		if( 0 == level[*it] )
		{
			GetEulerTur( *it, lev+1 );
			RMQ[0][++Index]=x;
		}
}
inline int log2N( int N )
{
	int l;
	for( l=0; (1<<l) <= N; ++l );
	return l-1;
}
inline int LCA( int x, int y )
{
	if( idx[x] > idx[y] )
		swap( x, y );
	int idxX=idx[x], idxY=idx[y], log2Idx;
	log2Idx=log2N( idxY-idxX+1 );
	if( level[RMQ[log2Idx][idxX]] <= level[RMQ[log2Idx][idxY-(1<<log2Idx)+1]] )
		return RMQ[log2Idx][idxX];
	return RMQ[log2Idx][idxY-(1<<log2Idx)+1];
}
int main()
{
	int N, M, x, y, log2Idx, i, j, till;
	ifstream in( "lca.in" );
	in>>N>>M;
	idx[0]=idx[1]=3*N;
	for( x=2; x <= N; ++x )
	{
		in>>y;
		idx[x]=3*N;
		G[y].push_back(x);
	}
	GetEulerTur( 1, 1 );
	log2Idx=log2N( Index );
	for( i=j=1; i <= log2Idx; ++i, j*=2 )
	{
		till=Index-2*j+1;
		for( x=1; x <= till; ++x )
			if( level[RMQ[i-1][x]] <= level[RMQ[i-1][x+j]] )
				RMQ[i][x]=RMQ[i-1][x];
			else RMQ[i][x]=RMQ[i-1][x+j];
	}
	ofstream out( "lca.out" );
	for( ; M; --M )
	{
		in>>x>>y;
		out<<LCA( x, y )<<'\n';
	}
	return EXIT_SUCCESS;
}