1  public int removeElement(int[] nums, int val) {

 2         int last = nums.length - 1;

 3         for (int i = 0; i <= last && last >= 0; i++) {

 4             while (last >= 0 && nums[last] == val) last--;

 5             if (last >= 0 && i < last && nums[i] == val) {

 6                 nums[i] = nums[last];

 7                 last--;

 8             }

 9         }

10         return last + 1;

11     }