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


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

	double A,B,C;

	A = a*a-b*b;	if(A<0) A=1e9;	A = sqrt(A);
	B = b*b-a*a;	if(B<0) B=1e9;	B = sqrt(B);
	C = a*a+b*b;	if(C<0) C=1e9;	C = sqrt(C);

	printf("%.10f\n", min(A, min(B, C)));


}