The organizers decided to order buses to visit the health camp. It is known that N children and M adults are going to the camp. Each bus can carry K people. There must be at least two adults on each bus that children travel on.
Determine whether it will be possible to send all children and adults to the camp, and if so, what is the minimum number of buses required to order.
Input
The input of the program is 3 natural numbers written with a space - N, M and K, each of them does not exceed 10 000.
Imprint
Print the number of buses to order. If it's impossible to send everyone to the camp, print 0 (zero).
Examples
| # |
Input |
Output |
| 1 |
10 4 7 |
2 |
| 2 |
10 4 5 |
0 |