longest-consecutive-sequence solution

Author: 이호찬

longest-consecutive-sequence/lhc0506.js

@@ -0,0 +1,31 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var longestConsecutive = function(nums) {
+    const numSet = new Set(nums);
+
+    let maxLength = 0;
+    let currentLength = 0;
+
+    nums.forEach(num => {
+        let currentNum = num;
+        while(numSet.has(currentNum)) {
+            numSet.delete(currentNum)
+            currentNum += 1;
+            currentLength += 1;
+        }
+
+        currentNum = num - 1;
+        while(numSet.has(currentNum)) {
+            numSet.delete(currentNum)
+            currentNum -= 1;
+            currentLength += 1;
+        }
+
+        maxLength = Math.max(maxLength, currentLength);
+        currentLength = 0;
+    });
+
+    return maxLength;
+};