Add files via upload

Author: AvinandanBose

HashSetDemo20.java

@@ -0,0 +1,19 @@
+import java.util.HashSet;
+
+public class HashSetDemo20 {
+
+    public static void main(String[] args) {
+        HashSet<String> set = new HashSet<>();
+        
+        set.add("A");
+        set.add("a");
+        set.add("B");
+        set.add("b");
+       
+        System.out.println(set);
+       
+        System.out.println(set.size());
+    }
+    
+    
+}