Problem: I have a sequence defined as follows:

* All even-numbered terms are equal to the previous term multiplied by 2.
* All odd-numbered terms are equal to the previous term divided by 3.



Create a program that reads the first term a of this sequence and outputs the sum s (10) from the first term to the tenth term.



Input

The input consists of multiple test cases. For each test case, a real number a (1.0 ≤ a ≤ 10.0) representing the first term of the sequence is given in one row.

The number of test cases does not exceed 50.

Output

Print s (10) on one line for each test case.

The output may contain an error of 0.000001 or less.

Example

Input

1.0
2.0
3.0


Output

7.81481481
15.62962963
23.44444444

Solution (in CPP):

Solution:
#include <iostream>
#include <iomanip>

using namespace std;

double sum10(double a){
  double sum=0;
  for(int i=0;i<10;i++){
    sum+=a;
    if(i%2)
      a/=3.0;
    else
      a*=2.0;
  }
  return sum;
}
int main(){
  double a;
  while(cin>>a){
    cout<<setprecision(10)<<sum10(a)<<endl;
  }
}