#include <iostream>#include <string.h>#include <math.h>using namespace std;#define MAX 1000void bubble_sort(int s[],int len){bool flag=true;for(int ii=len-1;ii>0&&flagii--){flag=false;for(int jj=0;jj<ii;jj++){if(s[jj]>s[jj+1]){int temp= s[jj];s[jj]=s[jj+1];s[jj+1] = temp;flag=true;}}}}int main(){int n;int stripy[MAX];memset(stripy,0,MAX*sizeof(int));cout.precision(3);cout.setf(ios::fixed);while (cin>>n){for (int ii=0;ii<n;ii++){cin>>stripy[ii];}bubble_sort(stripy,n);double newdata=stripy[n-1];for(int ii=n-2;ii>=0;ii--){newdata = 2*sqrt(newdata*stripy[ii]);}cout<<newdata<<endl;}return 0;}
