27.remove-element.py

class Solution(object):
    def removeElement(self, nums, val):
        """
        :type nums: List[int]
        :type val: int
        :rtype: int
        """

        k = 0
        for i in range(len(nums)):

            if nums[i] != val:
                nums[k] = nums[i]
                k += 1

        return k