📝 Docs: solved2 #240

Author: jangwonyoon

longest-consecutive-sequence/jangwonyoon.js

@@ -1,4 +1,6 @@
 /**
+ * solve 1
+ *
  * 시간 복잡도: O(n log n)
  * 공간 복잡도: O(n)
  *
@@ -31,3 +33,28 @@ var longestConsecutive = function(nums) {
 
     return result;
 };
+
+/**
+ * solve 2
+ *
+ * 시간 복잡도: O(n)
+ * 공간 복잡도: O(n)
+ *
+ * @param {number[]} nums
+ * @return {number}
+ */
+var longestConsecutive = function(nums) {
+    let longest = 0;
+    const numSet = new Set(nums);
+
+    for (const num of numSet) {
+        if (numSet.has(num - 1)) continue;
+        let length = 1;
+
+        while (numSet.has(num + length)) length++;
+
+        longest = Math.max(length, longest);
+    }
+
+    return longest;
+}