#include<cstdio>
const int N=100001;
int n,m,x,y,i,j,g,t,a[N],p[N][19],l[N];
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<19;j++)
        	p[i][j]=-1;
    for(j=1;j<19;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])
            x^=y^=x^=y;
        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]);
        }
    }
}