#include <cstdio>
#include <fstream>
#include <vector>

using namespace std;

#define N 200001

vector<int> v[100001];
int n,m,k,i,l,j,L[N],h[N],lg[N],F[100001],rmq[32][N<<1];

void df (int nd,int lv){
	h[++k]=nd;
	L[k]=lv;
	F[nd]=k;
	for(vector<int>::iterator it=v[nd].begin();it<v[nd].end();++it){
		df(*it,lv+1);
		h[++k]=nd;
		L[k]=lv;}}

inline int lca (int x,int y){
	int a=F[x],b=F[y],sol,s,dif;
	if(a>b)
		swap(a,b);
	dif=b-a+1;
	l=lg[dif];
	sol=rmq[l][a];
	s=dif-(1<<l);
	if(L[sol]>L[rmq[l][a+s]])
		sol=rmq[l][a+s];
	return h[sol];}

int main ()
{
	
	ifstream f ("lca.in");
	freopen ("lca.out","w",stdout);
	f>>n>>m;
	for(i=2;i<=n;++i){
		f>>j;
		v[j].push_back(i);}
	df(1,0);
	rmq[0][1]=1;
	for(i=2;i<=k;++i){
		lg[i]=lg[i>>1]+1;
		rmq[0][i]=i;}
	for(i=1;(1<<i)<k;++i)
		for(j=1;j+(1<<i)<=k;++j){
			l=1<<(i-1);
			rmq[i][j]=rmq[i-1][j];
			if(L[rmq[i-1][j+l]]<L[rmq[i][j]])
				rmq[i][j]=rmq[i-1][j+l];}
	for(;m;--m){
		f>>i>>j;
		printf("%d\n",lca(i,j));}
	
	return 0;}