Remove Element

class Solution 
{
public:
    int removeElement(vector<int>& nums, int val) 
    {
        int len = nums.size();
        int i = 0;
        while(i < len)
            nums[i] == val? (nums[i] = nums[--len]): ++i;
        return len;
    }
};

https://leetcode.com/problems/remove-element/