#include<bits/stdc++.h>
using namespace std;
int xxx(int n)
{
	int ans=0;
	while (n)
	{
		ans=ans+n%10;
		n/=10;
	}
	return ans;
}
int main()
{
	long long tmp=0;
	int n,m;
	cin>>n>>m;
	for (int i=n;i<=m;i++)
	{
		if (xxx(i*i)==xxx(i)*xxx(i)) 
			tmp++;
	}
	cout<<tmp;
	return 0;
}