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

def check(x):
    money = 0
    mul = x // A
    money += B * mul
    money += (x - mul)
    return money >= C

def main():
    ok = 10 ** 18
    ng = 0
    while abs(ok - ng) > 1:
        mid = (ok + ng) // 2
        if check(mid):
            ok = mid
        else:
            ng = mid

    print(ok)


if __name__ == "__main__":
    main()