[27] 移除元素

/**
 * @param {number[]} nums
 * @param {number} val
 * @return {number}
 */
var removeElement = function (nums, val) {
  let left = 0;
  let point = 0;
  while (point < nums.length) {
    if (nums[point] !== val) {
      nums[left] = nums[point]
      left++
    }
    point++
  }
  return left
};