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Author: AvinandanBose

HashSetDemo13.java

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+import java.util.HashSet;
+
+public class HashSetDemo13 {
+
+    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);
+
+        Boolean b = set.contains("A");
+
+        System.out.println(b);
+
+    }
+
+}