Code: Select all
#include <iostream>
#include <math.h>
using namespace std;
int isCom(int x,int y)
{
if(y==0) return x;
return isCom(y,x%y);
}
int main(){
int i,j,num;
int cNums;
int nums[51];
while(cin>>num)
{
if(num==0) break;
for(i=0;i<num;i++)
cin>>nums[i];
cNums=0;
for(i=num-1;i>=0;i--)
for(j=i-1;j>=0;j--)
{
//cout<<nums[i]<<" "<<nums[j]<<" "<<isCom(nums[i],nums[j])<<endl;
if(isCom(nums[i],nums[j])==1) cNums++;
}
num=num*(num-1)/2;
//cout<<num<<"*6/"<<cNums<<endl;
if(cNums==0)
cout<<"No estimate for this data set."<<endl;
else
cout<<(sqrt((double)(num*6)/cNums))<<endl;
}
return 0;
}