Remove Duplicates from Sorted Array II

Source

• lintcode: Remove Duplicates from Sorted Array II

Follow up for "Remove Duplicates":
What if duplicates are allowed at most twice?

For example,
Given sorted array A = [1,1,1,2,2,3],

Your function should return length = 5, and A is now [1,1,2,2,3].

Python

class Solution:
    """
    @param A: a list of integers
    @return an integer
    """
    def removeDuplicates(self, A):
        # write your code here
        if A is None or len(A)==0:
            return 0
        slow=0
        fast=1
        count=1
        while fast<len(A):
            if A[fast]==A[slow] and count<2:
                slow+=1
                A[slow]=A[fast]
                fast+=1
                count+=1
            elif A[fast]!=A[slow]:
                slow+=1
                A[slow]=A[fast]
                fast+=1
                count=1
            else:
                fast+=1
        # while fast<len(A):
        #     if A[fast]==A[slow] and count>=2:
        #         fast+=1
        #     else:
        #         tmp1 = slow
        #         tmp2 = fast
        #         slow+=1
        #         A[slow]=A[fast]
        #         fast+=1
        #         if A[tmp2]==A[tmp1]:
        #             count+=1
        #         else:
        #             count=1
        return slow+1