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

using ll = long long;
#define rep(i, n) for(int i = 0; i < n; i++)

int main() {
	int a, b;
	cin >> a >> b;
	if(a > b) swap(a, b);
	int d2 = b * b - a * a;
	if(a == b) d2 = a * a + b * b;
	double ans = sqrt(d2);
	cout << fixed << setprecision(12) << ans << endl;
}