B - Snail

Time limit: 1 s
Memory limit: 32 MiB
Languages: C, C++, Java, Python, ... (details)

There is a snail on the ground. It wants to climb to the top of a wooden pole with the height of $V$ meters, measuring from the ground level.

In one day it can climb $A$ meters upwards, however during each night it sleeps, sliding $B$ meters back down. Determine the number of days it needs to climb to the top.

Input

The first and only line of input contains three integers separated by a single space: $A$, $B$, and $V$ ($1 \leq B \lt A \leq V \leq 1 000 000 000$), with meanings described above.

Output

The first and only line of output must contain the number of days that the snail needs to reach the top.

Sample test(s)

Input
2 1 5
Output
4
Input
5 1 6
Output
2
Input
100 99 1000000000
Output
999999901