#include<iostream>
#include<cstdio>
using namespace std;
long long cool(long long a);
long long l,t;
int main()
{
	freopen("rabbits.in","r",stdin);
	freopen("rabbits.out","w",stdout);
	long long i,p,k,ans=0;
	scanf("%lld%lld",&l,&t);
	
	for(i=l;i<=t;i++)
	if(cool(i)*cool(i)==cool(i*i))
	{ans++;
	 //printf("%lld %lld\n",i,i*i);
//	 printf("%lld,",ans);
    }
	 
	 printf("%lld",ans);
	 return 0;
}
long long cool(long long a)
{
	long long total=0;
	while(a)
	{
		total+=a%10;
		a=a/10;
	}
	return total;
}