#include<cstdio>
#include<iostream>
#include<algorithm>
#include<string>
#include<queue>
#include<vector>
#include<functional>
#include<cmath>
#include<map>
#include<stack>
#include<set>
#include<numeric>

using namespace std;
typedef long long ll;
typedef pair<ll, ll> pl;

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

	int A = max(a, b), B = min(a, b);

	printf("%.20f\n",sqrt(A*A-B*B));
	return 0;
}