feat: contain-duplicate 작성

Author: hozzijeong

contains-duplicate/hozzijeong.js

@@ -0,0 +1,10 @@
+/**
+ * @param {number[]} nums
+ * @return {boolean}
+ */
+var containsDuplicate = function(nums) {
+    const originLength = nums.length;
+    const numsSet = new Set(nums);
+
+    return originLength !== numsSet.size;
+};