Problems

# Buy the water

# Buy the water

The cost of a bottle of water (including the cost of the empty bottle) is **1** dollar **20** cents. The cost of the empty bottle is **20** cents.

How many bottles of water is it possible to drink for **n** dollars, if you can recycle bottles for cash and buy new bottles of water for this cach.

#### Input

Positive integer **n** (**1** ≤ **n** ≤ **1000**).

#### Output

Number of bottles of water that you can drink for **n** dollars.

Input example

2

Output example

1

**Example description:**
You canot buy the water without a bottle