#include<cstdio>
#include<vector>
#define pb push_back
using namespace std;
#define minn(a,b) ((a<b)?a:b)
#define N 100001
int e[20][N<<2],n,m,x,y,dep[20][N<<2],lung,jum;
vector<int>arb[N],pr(N,0),d(N,0),log(N,0);
void df(int x)
{
	e[0][++e[0][0]]=x;
	dep[0][e[0][0]]=d[x];
	if (!pr[x])
		pr[x]=e[0][0];
	size_t g=arb[x].size();
	for (size_t i=0; i<g; ++i)
	{
		d[arb[x][i]]=1+d[x];
		df(arb[x][i]);
		e[0][++e[0][0]]=x;
		dep[0][e[0][0]]=d[x];
	}
}
void rmq()
{
	int i;
	log[2]=1;
	for(i=3; i<=e[0][0]; ++i)
		log[i]=log[i>>1]+1;
	for (int i=1; i<=log[e[0][0]]; ++i)
	{
		lung=1<<i;
		jum=lung>>1;
		for(int j=1; j+lung-1<=e[0][0]; ++j)
			if(dep[i-1][j]<dep[i-1][j+jum])
			{
				dep[i][j]=dep[i-1][j];
				e[i][j]=e[i-1][j];
			}
			else
			{
				dep[i][j]=dep[i-1][j+jum];
				e[i][j]=e[i-1][j+jum];
			}
	}
}
void solve()
{
	if (pr[x]>pr[y])
		swap(x,y);
	int dim=pr[y]-pr[x]+1;
	int lo=log[dim];
	if(dep[lo][pr[x]]<dep[lo][pr[y]-dim+1])
		x=e[lo][pr[x]];
	else
		x=e[lo][pr[y]-dim+1];
}
void citire()
{
	freopen("lca.in","r",stdin);
	freopen("lca.out","w",stdout);
	scanf("%d%d",&n,&m);
	for (int i=2; i<=n; ++i)
	{
		scanf("%d",&x);
		arb[x].pb(i);
	}
	df(1);
	/*for (int i=1; i<=e[0][0]; ++i)
		printf("%d %d\n",e[0][i],dep[0][i]);*/
	rmq();
	/*for (int i=0; i<=log[e[0][0]]; ++i)
	{
		for(int j=1; j<=e[0][0]; ++j)
			printf("%d ",dep[i][j]);
		printf("\n");
	}*/
	while (m--)
	{
		scanf("%d%d",&x,&y);
		solve();
		printf("%d\n",x);
	}
}
int main()
{
	citire();
	return 0;
}