## Exercise 1.1 ```python def zorglub(n: int) -> int: j = 1 k = 0 i = 1 while i <= n: j = i * j k = j + k i = i + 1 return k ``` The function return the sum of the factorial of n ## Exercise 1.2 ``` def multiplication(x: int, y: int) -> int: result = 0 for i in range(y): result = result + x return result def multiplication2(x: int, y: int) -> int: result = 0 if x < 0 and y < 0: i = 0 x = -x y = -y while i < y: result = result + x i += 1 return result elif y < 0: y = -y i = 0 while i < y: result = result + x i += 1 return -result else: i = 0 while i < y: result = result + x i += 1 return result ``` ## Exercise 1.3 ``` def exponentiation(x: int, n: int) -> int: