feat: contains-duplicate solve

Author: Real-Reason

contains-duplicate/Real-Reason.kt

@@ -0,0 +1,10 @@
+package leetcode_study
+
+class Solution {
+    fun containsDuplicate(nums: IntArray): Boolean {
+        val size = nums.size
+        val numsToSet = nums.toSet()
+
+        return size != numsToSet.size
+    }
+}