#include <cmath>
#include <ctime>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;

#define ll long long

ll S(ll x){
	ll sum = 0;
	while(x){
		sum += x%10;x /= 10;
	}return sum;
}

bool Check(ll x){
	while(x){
		if((x%10) > 3) return false;
		x /= 10;
	}return true;
}

ll qpow(ll x,ll k){
	ll ans = 1;
	if(k == 0) return 1;
	if(k == 1) return x;
	while(k){
		if(k&1) ans *= x;
		k >>= 1;x = x*x;
	}return ans;
}

ll up(ll x){
	ll a = x,cnt = 0;
	while(x){
		cnt ++;
		x /= 10;
	}
	ll tmp = qpow(10,cnt-1);
	tmp = a/tmp;
	if(tmp>3) return qpow(10,cnt)-1;
	return a;
}

int main(){
	freopen("rabbits.in","r",stdin);
	freopen("rabbits.out","w",stdout);
	ll l, r;scanf("%lld%lld",&l,&r);
	ll ans = 0;
	for(ll i = l;i <= r;i ++){
		i = up(i);
		ll t1 = S(i);
		t1 = t1*t1;
		ll t2 = S(i*i);
		if(t1 == t2){ans ++;}
	}
	printf("%lld\n",ans);
	//system("pause");
	return 0;
}