1. var longestConsecutive = function(nums) {
    2.     if (nums.length === 0) return 0;
    3.     const set = new Set(nums);
    4.     const n = nums.length;
    5.     let globalLongest = 1;
    6.     for (let i = 0; i < n; i++) {
    7.         if (!set.has(nums[i] - 1)) {
    8.             let longest = 1;
    9.             let currentNum = nums[i];
    10.             while (set.has(currentNum + 1)) {
    11.                 currentNum += 1;
    12.                 longest++;
    13.             }
    14.             globalLongest = Math.max(globalLongest, longest);
    15.         }
    16.     }
    17.     return globalLongest;
    18. };