import sys

A, B, C = map(int, input().split())


def total(n):
    return (n // A) * B + n - (n // A)

low = 0
high = 1000000000000000000
n = (low + high) // 2

while True:
    if total(n) >= C and total(n - 1) < C:
        print(n)
        sys.exit()
    elif total(n) > C:
        high = n - 1
    elif total(n) < C:
        low = n + 1
    n = (low + high) // 2