#include<bits/stdc++.h> using namespace std; double max(double x,double y,double z){ if(x<y) x=y; if(x<z) x=z; return x; }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; }