#include<stdio.h>
int n,m,x,y,i,j,g,t,a[100001],p[100001][20],l[100001];
int main() {
	freopen("lca.in","r",stdin),freopen("lca.out","w",stdout),scanf("%d%d",&n,&m),l[1]=1;
	for(i=2;i<=n;i++)
       	scanf("%d",&a[i]),l[i]=l[a[i]]+1,p[i][0]=a[i];
	for(i=0;i<=n;i++)
	for(j=1;j<=18;j++)
       	p[i][j]=-1;
	for(j=1;j<=18;j++)
	for(i=0;i<=n;i++)
	if(p[i][j-1]!=-1)
       	p[i][j]=p[p[i][j-1]][j-1];
	while(m--) {
		scanf("%d%d",&x,&y);
       	if(l[x]<l[y])
            t=x,x=y,y=t;
       	for(g=1;(1<<g)<=l[x];g++);
       	for(i=--g;i>=0;i--)
       	if(l[x]-(1<<i)>=l[y])
            x=p[x][i];
       	if(x==y)
            printf("%d\n",x);
       	else {
		   	for(i=g;i>=0;i--)
            if(p[x][i]!=-1&&p[x][i]!=p[y][i]&&p[y][i]!=-1)
                x=p[x][i],y=p[y][i];
            printf("%d\n",a[x]);
		}
	}
}