There is a snail on the ground. It wants to climb to the top of a wooden pole with a 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 Specification

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

Output Specification

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

Sample Input 1

2 1 5

Sample Output 1

4

Sample Input 2

5 1 6

Sample Output 2

2

Sample Input 3

100 99 1000000000

Sample Output 3

999999901