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<math.h>
#include<vector>
#include<algorithm>
#include<cstdio>
using namespace std;

int main() {
  double a;
  while(cin>>a){
    double ans = a;
    for(int i=2;i<=10;i++) {
      if (i%2==1)
        a/=3;
      else
        a*=2;
      ans += a;
    }
    printf("%.8lf\n",ans);
  }
}