Improve the following code in Python to find the product of two given numbers without using the multiply operator.
def multiply(x, y):
    result = 0
    for i in range(x):
        result += y
    return result
def multiply(x, y):
    result = 0
    for i in range(y):
        result += x
    return result

def power(x, y):
    result = 1
    for i in range(y):
        result *= x
    return result