Merge pull request #1998 from ljh981009/main

[ljh981009] WEEK 01 solutions

Author: TonyKim9401

contains-duplicate/ljh981009.ts

@@ -0,0 +1,4 @@
+function containsDuplicate(nums: number[]): boolean {
+  const result = new Set(nums);
+  return result.size !== nums.length;
+}