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 s, sum;

	while (cin >> s){
		s *= 3;
		sum = s;
		for (int i = 0; i < 4; i++){
			s *= 2.0 / 3.0;
			sum += s;
		}
		printf("%.7lf\n", sum);
	}
	return (0);
}