def binary_search(A, B, C):
    left, right = 1, 10 ** 18

    while left <= right:
        mid = (left + right) // 2
        m = mid // A
        money = m * B + mid - m
        
        if money < C:
            left = mid + 1
        else:
            right = mid - 1
    
    return left

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