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 <stdio.h>

using namespace std;

int main(int argc, char **argv)
{
	double a, tmp;
	
	while(cin >> a){
		tmp = a;
		a *= 2;
		tmp += a;
		for(int i = 1; i < 5; i++){
			a /= 3;
			tmp += a;
			a *= 2;
			tmp += a;
		}
		
		printf("%.8lf\n", tmp);
	}
	
	return 0;
}