#include <iostream>
#include <cmath>
#include <iomanip>
using namespace std;

int main()
{
	int a, b;
	double c;
	cin >> a >> b;

	if (a > b) {
		c = sqrt(a*a - b*b);
	}
	else if (a < b) {
		c = sqrt(b*b - a*a);
	}
	else {
		c = sqrt(a*a + b*b);
	}

	cout << fixed << setprecision(7) << c << endl;

    return 0;
}