c++

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