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

double f(double a,double b,double c){
    return max(max(a,b),c);
}
       
int main(){
    double a,b,c;
    double m;
    cin>>a>>b>>c;
    m=f(a,b,c)*1.0/f(a+b,b,c)/f(a,b,b+c);
    printf("%.3f",m);
}