Competitions
Week 2 Conditionals Part 1
Sightseeing trip
The pupils from 10-B class decided in the autumn holiday to go on an excursion to the capital. Knowing the number of boys n and girls m, determine how many rooms you need to book in a hotel, if each room has k beds and it is forbidden to settle boys and girls together.
Input data
One line contains three numbers n, m, k (n, m, k ≤ 100).
Output data
Print one number - the number of rooms to book in the hotel.
Examples
Input example #1
6 12 3
Output example #1
6