2869 달팽이는 올라가고 싶다

import sys

sys.stdin = open("input.txt","rt")

up,down,v = map(int, sys.stdin.readline().split())

total_v = 0

cnt = 0


while True:

    cnt += 1

    total_v += up

    if total_v >= v:
        break

    else:
        total_v -= down


print(cnt)

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# 답


import sys
import math

sys.stdin = open("input.txt","rt")

a,b,v = map(int, sys.stdin.readline().split())

total_day = math.ceil((v-b)/(a-b))


print(total_day)