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 <bits/stdc++.h>

using namespace std;

int main() {
    double sq[11];
    while (scanf("%lf", &sq[1]) != EOF) {
        double ans = sq[1];

        for (int i = 2; i <= 10; i++) {
            if (i % 2) sq[i] = sq[i - 1] / 3.0;
            else sq[i] = sq[i - 1] * 2.0;
            ans += sq[i];
        }

        printf("%.10f\n", ans);
    }

    return 0;
}