Contains Duplicate Solution

Author: river20s

contains-duplicate/river20s.java

@@ -0,0 +1,15 @@
+import java.util.HashSet;
+
+class Solution {
+    public boolean containsDuplicate(int[] nums) {
+        HashSet<Integer> set = new HashSet<>();
+        
+        for (int num : nums) {
+		        if (!set.add(num)) {
+				        return true;
+		        }
+		    }
+		    
+		    return false;
+    }
+}