#include<cstdio>
#include<vector>
using namespace std;

int n,m,i,j,x,y,first[100010],LG[100010],E[200010],e,D[200010],d,rmq[18][200010],LCA(int,int);
vector<int> T[100010];

void read(),solve(),euler(int,int);

int main()
{
	read();
	solve();
	
	return 0;
}

void read()
{
	freopen("lca.in","r",stdin);
	freopen("lca.out","w",stdout);
	scanf("%d%d",&n,&m);
	for(i=2;i<=n;i++)
	{
		scanf("%d",&x);
		T[x].push_back(i);
		LG[i]=LG[i>>1]+1;
	}
}

void solve()
{
	euler(1,0);
	for(i=1;i<=d;i++)rmq[0][i]=i;
	for(i=1;(1<<i)<=d;i++)
	{
		for(j=1;j+(1<<i)<d;j++)
		{
			int l=1<<(i-1);
			rmq[i][j]=rmq[i-1][j];
			if(D[rmq[i-1][j+l]]<D[rmq[i][j]])
				rmq[i][j]=rmq[i-1][j+l];
		}
	}
	for(;m--;)
	{
		scanf("%d%d",&x,&y);
		printf("%d\n",E[LCA(first[x],first[y])]);
	}
}

void euler(int node,int depth)
{
	E[++e]=node;
	D[++d]=depth;
	if(!first[node])first[node]=e;
	for(vector<int>::iterator it=T[node].begin();it!=T[node].end();it++)
	{
		int aux=*it;
		if(!first[aux])
			euler(aux,depth+1);
		E[++e]=node;
		D[++d]=depth;
	}
}

int LCA(int beg,int end)
{
	if(beg>end){int aux=beg;beg=end;end=aux;}
	int log=LG[end-beg+1];
	int l=1<<log;
	int sol=rmq[log][beg];
	if(D[sol]>D[rmq[log][end-l+1]])
		sol=rmq[log][end-l+1];
	return sol;
}