leetcode-26 删除排序数组中的重复项

/**
 * @param {number[]} nums
 * @return {number}
 */
var removeDuplicates = function (nums) {
  // 双指针
  let left = (right = 0);
  while (right < nums.length) {
    // 找到第一个不等于left的元素
    while (nums[right] === nums[left]) {
      right++;
    }
    if (right < nums.length && nums[left] !== nums[right]) {
      if (right > left + 1) {
        nums[left + 1] = nums[right];
      }
      left++;
    }
    right++;
  }
  return left + 1;
};
// removeDuplicates([1, 1, 2]);
// removeDuplicates([1, 1]);
// removeDuplicates([0, 0, 1, 1, 1, 2, 2, 3, 3, 4]);

/**
 * @param {number[]} nums
 * @param {number} k
 * @return {void} Do not return anything, modify nums in-place instead.
 */
var rotate = function (nums, k) {
  const length = nums.length;
  const count = k % length;
  if (count === 0) return;
  // 翻转
  function reverse(left, right) {
    while (left < right) {
      [nums[left], nums[right]] = [nums[right], nums[left]];
      left++;
      right--;
    }
  }
  reverse(0, length - 1);
  reverse(0, count - 1);
  reverse(count, length - 1);
};
// rotate([1, 2, 3, 4, 5, 6, 7], 3);