#include <iostream>
using namespace std;
double max(double a, double b, double c)
{
if (a < b)
swap(a, b);
if (a < c)
swap(a, c);
return a;
}
int main()
{
double a, b, c;
cin >> a >> b >> c;
double m = max(a, b, c) / (max(a + b, b, c) * max(a, b, b + c));
printf("%.3lf", m);
return 0;
}