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<cstdio>

using namespace std;

int main(void){
	double a;
	
	while(scanf("%lf", &a) != EOF){
		double n[11];
		n[1] = (double)a;
		
		for(int i = 2; i < 11; i++){
			if(i%2){
				n[i] = n[i-1]/3;
			}else{
				n[i] = n[i-1]*2;
			}
		}
		
		double ans = 0;
		for(int i = 1; i < 11; i++){
			ans += n[i];
		}
		
		printf("%lf\n", ans);
	}
	return 0;
}