Merge pull request #1143 from itsChrisJang/main

[itschrisjang] WEEK 01 solutions

Author: itsChrisJang

contains-duplicate/itschrisjang.java

@@ -0,0 +1,17 @@
+import java.util.HashSet;
+
+class Solution {
+	public boolean containsDuplicate(int[] nums) {
+		HashSet<Integer> numSet  = new HashSet<>();
+    
+		for (int i = 0; i < nums.length; i++) {
+
+			if (numSet.contains(nums[i])) {
+				return true;
+			}
+			numSet.add(nums[i]);
+		}
+    
+		return false;
+	}
+}