#include <iostream>
#include <iomanip>
#include <algorithm>
#include <cmath>

using namespace std;

int main() {
	double a, b;
	cin >> a >> b;
	double c1 = abs(b * b - a * a);
	double c2 = a * a + b * b;
	cout << fixed << setprecision(7) << sqrt(c1 == 0.0 ? c2 : min(c1, c2)) << endl;
	return 0;
}