[15] 三数之和

// @lc code=start
/**
 * @param {number[]} nums
 * @return {number[][]}
 */
var threeSum = function (nums) {
  const lists = [];
  nums.sort((a, b) => a - b);
  let i = 0;
  let y = 0;
  for (i = 0; i < nums.length - 2; i++) {
    if (i > 0 && nums[i] === nums[i - 1]) continue;
    y = i + 1;
    for (let j = nums.length - 1; j > y;) {
      if (j < nums.length - 1 && nums[j] === nums[j + 1]) {
        j--;
        continue;
      }
      if (nums[i] + nums[j] + nums[y] === 0) {
        lists.push([nums[i], nums[j], nums[y]]);
        j--;
        y++;
      }
      if (nums[i] + nums[j] + nums[y] > 0) j--;
      if (nums[i] + nums[j] + nums[y] < 0) y++;
    }
  }
  return lists;
};