content: package by.andd3dfx.common;
  
  /**
   * <pre>
   * <a href="https://leetcode.com/problems/remove-element/">Task description</a>
   *
   * Given an integer array nums and an integer val, remove all occurrences of val in nums in-place. The order of the
   * elements may be changed. Then return the number of elements in nums which are not equal to val.
   *
   * Consider the number of elements in nums which are not equal to val be k, to get accepted, you need to do the
   * following things:
   * - Change the array nums such that the first k elements of nums contain the elements which are not equal to val.
   * The remaining elements of nums are not important as well as the size of nums.
   * - Return k.
   *
   * Example 1:
   *
   * Input: nums = [3,2,2,3], val = 3
   * Output: 2, nums = [2,2,_,_]
   * Explanation: Your function should return k = 2, with the first two elements of nums being 2.
   * It does not matter what you leave beyond the returned k (hence they are underscores).
   *
   * Example 2:
   *
   * Input: nums = [0,1,2,2,3,0,4,2], val = 2
   * Output: 5, nums = [0,1,4,0,3,_,_,_]
   * Explanation: Your function should return k = 5, with the first five elements of nums containing 0, 0, 1, 3, and 4.
   * Note that the five elements can be returned in any order.
   * It does not matter what you leave beyond the returned k (hence they are underscores).
   * </pre>
   *
   * @see <a href="https://youtu.be/ECdosiz1ZPM">Video solution</a>
   */
  public class RemoveElement {
  
      public static int removeElement(int[] nums, int val) {
          var count = nums.length;
  
          var left = 0;
          var right = 0;
          while (right < nums.length) {
              // Skip all items that equals to `val`
              while (right < nums.length && nums[right] == val) {
                  right++;
                  count--;
              }
  
              // Copy from right side to left side all items that not equals to `val`
              // (until we found item equals to `val` or array finished)
              while (right < nums.length && nums[right] != val) {
                  nums[left] = nums[right];
                  left++;
                  right++;
              }
          }
  
          return count;
      }
  }
  