Little Red Riding Hood often visits her grandmother. But she is very afraid that sooner or later the wolf will visit her grandmother again. Therefore, she decided to negotiate with the Forester about the protection of her grandmother. The forester agreed to guard the grandmother for 10 pies.
Upon learning of this, the wolf told Little Red Riding Hood that she absolutely did not need to spend pies on the Forester. For half of those pies that Little Red Riding Hood brings to her grandmother, the Wolf promised not to touch her.
Today (November 26) is Mother's Day in Russia. Mom baked some pies and asked Little Red Riding Hood to take them to Grandma. It is required to determine how many pies Little Red Riding Hood can bring to her grandmother.
Input
One even number is entered - the number of pies that mom baked.
Imprint
The program should print one number - the number of pies that Little Red Riding Hood can bring to her grandmother.
Examples
| # |
Input |
Output |
| 1 |
12 |
6 |
| 2 |
100 |
90 |