leetcode之Remove Duplicates from Sorted Array II

这题第一个方法就是采用counter这个python自带的高级语法来解决了，简单。代码如下：

from collections import Counter
        a = Counter(nums)        
        for i in a.keys():
            if a[i] > 2:             
                for j in range(a[i] - 2):
                    nums.remove(i)        
        return len(nums)

自然也可以采用文章推荐的方法。

class Solution(object):
    def removeDuplicates(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        if nums == []:
            return 0
        if len(nums) < 3:
            return len(nums)
        prev = nums[-1]
        p = 2
        for i in range(2,len(nums))[::-1]:
            # print i - 2
            if prev == nums[i - 2]:
                # print nums[i - 2]
                del nums[i - 2]
                # print nums
                continue
            p = p + 1
            prev = nums[i - 1]
        # print nums
        return p

可惜不会删除的好方法。。。所以时间上还是拖的有点多