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

int main(){
	int a, b;
	cin >> a >> b;
	double ans;
	if(a == b){
		ans = a * a * 2.;
		ans = sqrt(ans);
	}else{
		ans = (double)(max(a, b) * max(a, b)) - (min(a, b) * min(a, b));
		ans = sqrt(ans);
	}
	printf("%.10f\n", ans);
	
}