import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

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

def f(x):
    n = x // A
    return (x-n) + B * n

left = 0  # C 未満
right = C  # C以上

while left + 1 < right:
    x = (left + right) // 2
    if f(x) < C:
        left = x
    else:
        right = x

answer = right
print(answer)