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 <cstdio>
using namespace std;

int main(){
  double a,an,sum;
  while(cin>>a){
    an=a*2;
    sum=0;
    for(int i=0;i<5;i++){
      sum+=a+an;
      a=an/3;
      an=a*2;
    }
    printf("%.8lf\n",sum);
  }
  return 0;
}