#70 백준 파이썬 [2869] 달팽이는 올라가고 싶다

https://www.acmicpc.net/problem/2869

 

 

#Solution

A, B, V = map(int, input().split())
min_days = (V - A) / (A - B)

if min_days == round(min_days):
    print(int(min_days + 1))
else:
    print(round(min_days+1.5))