leet 128 longest consecutive sequences [medium]

Author: hyeonbinHur

허현빈/5주차/260126.js

@@ -0,0 +1,25 @@
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var longestConsecutive = function (nums) {
+  const set = new Set(nums);
+
+  let max = 0;
+  for (let num of set) {
+    let count = 1;
+    if (!set.has(num - 1)) {
+      let idx = 1;
+      while (1) {
+        if (set.has(num + idx)) {
+          idx++;
+          count++;
+        } else {
+          break;
+        }
+      }
+      max = Math.max(max, count);
+    }
+  }
+  return max;
+};