#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

int main() {
	int a, b;
	cin >> a >> b;
	int ma = max(a, b);
	int mi = min(a, b);
	int n = ma * ma - mi * mi;
	ll n2 = n;
	ll ans = 0;
	for (int i = 0;i < 10;i++) {
		int c = 0;
		while ((ans+1)*(ans+1) <= n2) {
			ans++;
			c++;
		}
		ans *= 10;
		n2 *= 100;
		cout << c;
		if (i == 0) {
			cout << '.';
		}
	}
	cout <<endl;

	return 0;
}