ARRAY_EXCEPT

ARRAY_EXCEPT(A, B)

Takes in two arrays and returns a copy of the first array but with all of the elements from the second array dropped. If an element appears in the first array more than once, that element is only dropped as many times as it appears in the second array. For instance, if the first array contains three 1s and four 6s, and the second array contains two 1s and one 6, then the output will have one 1 and three 6s.