Given an array and a value, remove all instances of that value in place and return the new length.
The order of elements can be changed. It doesn‘t matter what you leave beyond the new length.
双指针基本操作,每个符合要求的都放在前面
class Solution: def removeElement(self, nums, val): i, j= 0, 0 while i < len(nums): if nums[i] != val: nums[j] = nums[i] j += 1 i += 1 return j
这里用的是copy防止操作影响最后返回的list
class Solution: def removeElement(self, nums, val): nums[:] = [x for x in nums if x != val] return len(nums)
原文：http://www.cnblogs.com/lilixu/p/4615950.html