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 PYTHON):

Solution:
import sys
def S(a,r,n):
    if r==1:return n*a
    a,r,n=map(float,[a,r,n])
    return a*(1.0-r**(n))/(1.0-r)
for line in sys.stdin.readlines():
    n=float(line.strip())
    print S(n,2.0/3.0,5)+S(n*2,2.0/3.0,5)