#include<cstdio>
int m,n,i,j,k,x,y,a[200000],rmq[20][200000],poz[100013],ln[20],lev[100013];
struct point
{
	int x;
	point *y;
}*g[1000013],*p;
inline int min(const int &a, const int &b)
{
	return(lev[a]<lev[b]?a:b);
}
void go(const int &nod)
{
	a[n]=rmq[0][n]=nod;
	poz[nod]=n;
	++n;
	point *p;
	for(p=g[nod];p!=NULL;p=p->y) 
	{
		lev[p->x]=lev[nod]+1;
		go(p->x);
		a[n]=rmq[0][n]=nod;
		poz[nod]=n;
		++n;
	}
}
int main()
{
	freopen("lca.in","r",stdin);
	freopen("lca.out","w",stdout);
	scanf("%d%d",&n,&m);
	for(i=2;i<=n;++i)
	{
		scanf("%d",&x);
		point *p=new point;
		p->x=i;
		p->y=g[x];
		g[x]=p;
	}
	n=0;
	lev[1]=0;
	go(1);
	ln[1]=0;
	for(i=2;i<=n;++i)ln[i]=ln[i/2]+1;
	for(i=1;(1<<i)<=n;++i)
		for(j=0;j<=n-(1<<(i-1));++j)
			rmq[i][j]=min(rmq[i-1][j],rmq[i-1][j+(1<<(i-1))]);
	for(i=0;i<m;++i)
	{
		scanf("%d%d",&x,&y);
		x=poz[x];y=poz[y];
		if(x>y) {j=x;x=y;y=j;}
		y-=(x-1);
		k=ln[y];
		y-=(1<<k);
		printf("%d\n",min(rmq[k][x],rmq[k][x+y]));
	}
	return 0;
}