python之lintcode刷题：Find The Numbers II

Given two numbers A and B, find out all the numbers which are the multiple of 3 between A and B (including A and B). Return the sum of these numbers.
代码：

def getSum(A, B):
    # Write your code here
    sum = 0
    for i in range(A,B+1):
        if i % 3 == 0:
            sum += i
    return sum