Conatins Duplicate solution

Author: yuhyeon99

contains-duplicate/yuhyeon99.js

@@ -0,0 +1,12 @@
+/**
+ * @param {number[]} nums
+ * @return {boolean}
+ */
+var containsDuplicate = function(nums) {
+    let numsSet = new Set();
+    for(let i = 0; i < nums.length; i ++) {
+        if(numsSet.has(nums[i])) return true;
+        numsSet.add(nums[i])
+    }
+    return false;
+};