#include <iostream>
#include <stdio.h>
#include <math.h>
using namespace std;
int main(int argc, char* argv[])
{
	int a,b;
	cin>>a>>b;
	if (a<b){
		swap(a,b);
	}
	double c1,c2;
	c1=a*a+b*b;
	c2=a*a-b*b;
	double C1=sqrt(c1);
	double C2=sqrt(c2);
	printf("%.10lf\n",min(C1,C2));
	return 0;
}