#include <algorithm>
#include <cstdio>
#include <ctype.h>
#include <functional>
#include <iostream>
#include <iomanip>
#include <cassert>
#include <cfloat>
#include <climits>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <time.h>
#include <vector>
#include <iomanip>
using namespace std;
int main() {
	int a,b;
	cin >> a>>b;

	if (a <= b) {
		swap(a, b);
	}
	cout
		<< fixed
		<< setprecision(10)
	<< sqrt(a*a - b*b) << endl;
	return 0;
}