/*This is a Java program to Implement Tree Set. A set is an abstract data structure that can store certain values, without any particular order, and no repeated values. Here Tree set maintains sorted order.*/ /** * Java program to implement Tree Set */ import java.util.Scanner; /** class TreeSetNode **/ class TreeSetNode { String data; TreeSetNode left, right; /** constructor **/ public TreeSetNode(String data, TreeSetNode left, TreeSetNode right) { this.data = data; this.left = left; this.right = right; } } /** class TreeSet **/ class TreeSet { private TreeSetNode root; private int size; /** constructor **/ public TreeSet() { root = null; size = 0; } /** function to check if empty **/ public boolean isEmpty() { return root == null; } /** function to clear **/ public void clear() { root = null; size = 0; } /** function to insert an element **/ public void add(String ele) { root = insert(root, ele); } /** function to insert an element **/ private TreeSetNode insert(TreeSetNode r, String ele) { if (r == null) r = new TreeSetNode(ele, null, null); else { if (ele.compareTo(r.data) < 0) r.left = insert(r.left, ele); else if (ele.compareTo(r.data) > 0) r.right = insert(r.right, ele); } return r; } /** Functions to count number of nodes **/ public int countNodes() { return countNodes(root); } /** Function to count number of nodes recursively **/ private int countNodes(TreeSetNode r) { if (r == null) return 0; else { int l = 1; l += countNodes(r.left); l += countNodes(r.right); return l; } } /** Functions to search for an element **/ public boolean contains(String ele) { return contains(root, ele); } /** Function to search for an element recursively **/ private boolean contains(TreeSetNode r, String ele) { boolean found = false; while ((r != null) && !found) { if (ele.compareTo(r.data) < 0) r = r.left; else if (ele.compareTo(r.data) > 0) r = r.right; else { found = true; break; } found = contains(r, ele); } return found; } /** Function to delete data **/ public void delete(String ele) { if (isEmpty()) System.out.println("Tree Empty"); else if (contains(ele) == false) System.out.println("Error : "+ ele +" is not present"); else { root = delete(root, ele); System.out.println(ele +" deleted from the tree set"); } } /** Function to delete element **/ private TreeSetNode delete(TreeSetNode r, String ele) { TreeSetNode p, p2, n; if (r.data.equals(ele)) { TreeSetNode lt, rt; lt = r.left; rt = r.right; if (lt == null && rt == null) return null; else if (lt == null) { p = rt; return p; } else if (rt == null) { p = lt; return p; } else { p2 = rt; p = rt; while (p.left != null) p = p.left; p.left = lt; return p2; } } if (ele.compareTo(r.data) < 0) { n = delete(r.left, ele); r.left = n; } else { n = delete(r.right, ele); r.right = n; } return r; } /** function toString() **/ public String toString() { return "[ "+ inorder(root, "") +"]"; } private String inorder(TreeSetNode r, String str) { if (r != null) return str + inorder(r.left, str) + r.data +" "+ inorder(r.right, str); else return ""; } } /** Class TreeSetTest **/ public class TreeSetTest { public static void main(String[] args) { Scanner scan = new Scanner(System.in); /** Creating object of TreeSetTest **/ TreeSet ts = new TreeSet(); System.out.println("Tree Set Test\n"); char ch; /** Perform set operations **/ do { System.out.println("\nTree Set Operations\n"); System.out.println("1. add "); System.out.println("2. delete"); System.out.println("3. contains"); System.out.println("4. count "); System.out.println("5. check empty"); System.out.println("6. clear"); int choice = scan.nextInt(); switch (choice) { case 1 : System.out.println("Enter element to insert"); ts.add( scan.next() ); break; case 2 : System.out.println("Enter element to delete"); ts.delete( scan.next() ); break; case 3 : System.out.println("Enter integer element to search"); System.out.println("Search result : "+ ts.contains( scan.next() )); System.out.println(); break; case 4 : System.out.println("Count = "+ ts.countNodes()); break; case 5 : System.out.println("Empty status = "+ ts.isEmpty()); break; case 6 : System.out.println("Tree set cleared"); ts.clear(); break; default : System.out.println("Wrong Entry \n "); break; } /** Display tree set **/ System.out.print("\nTree Set : "+ ts); System.out.println(); System.out.println("\nDo you want to continue (Type y or n) \n"); ch = scan.next().charAt(0); } while (ch == 'Y'|| ch == 'y'); } } /* Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 5 Empty status = true Tree Set : [ ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 1 Enter element to insert mango Tree Set : [ mango ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 1 Enter element to insert strawberry Tree Set : [ mango strawberry ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 1 Enter element to insert apple Tree Set : [ apple mango strawberry ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 1 Enter element to insert pineapple Tree Set : [ apple mango pineapple strawberry ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 1 Enter element to insert orange Tree Set : [ apple mango orange pineapple strawberry ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 1 Enter element to insert jackfruit Tree Set : [ apple jackfruit mango orange pineapple strawberry ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 4 Count = 6 Tree Set : [ apple jackfruit mango orange pineapple strawberry ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 2 Enter element to delete jackfruit jackfruit deleted from the tree set Tree Set : [ apple mango orange pineapple strawberry ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 2 Enter element to delete strawberry strawberry deleted from the tree set Tree Set : [ apple mango orange pineapple ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 3 Enter integer element to search strawberry Search result : false Tree Set : [ apple mango orange pineapple ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 4 Count = 4 Tree Set : [ apple mango orange pineapple ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 5 Empty status = false Tree Set : [ apple mango orange pineapple ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 6 Tree set cleared Tree Set : [ ] Do you want to continue (Type y or n) y Tree Set Operations 1. add 2. delete 3. contains 4. count 5. check empty 6. clear 5 Empty status = true Tree Set : [ ] Do you want to continue (Type y or n) n