image.png
解法一（84 ms 52.79%）：
class Solution(object):
def removeDuplicates(self, nums):
"""
:type nums: List[int]
:rtype: int
"""
if len(nums)==0:
return 0
if len(nums)==1:
return 1
k=0
for i in range(len(nums)-1):
if nums[i]!=nums[i+1]:
nums[k+1]=nums[i+1]
k+=1
del nums[k+1:]
return len(nums)
