You all know what is a notebook? A notebook is a copy (In regular language) in which we write notes. A page in a notebook has 19 lines. And you have to find the total number of lines in the notebook? Provided the user will tell you if it’s an inter-leaf notebook (lines on just one side) or a regular notebook (Which has lines on both sides of the pages). The number of pages in the notebook has to be taken from the user.

NB: The user will enter 1 for inter-sleaf and 2 for a regular notebook.

Constraints:

Number of pages, n<2000

Input

1

250

Explanation:

1 represents an interleaf notebook, 250 is the number of pages. So pages containing lines will be 250/2=125. So total number of lines will be 125*19=2375

Output

2375

Input

2

360

Explanation:

2 represents a regular notebook, 360 is the number of pages. So pages containing lines will be 360. So total number of lines will be 360*19=6840

Output

6840