Merge pull request #16 from mehmetpekdemir/develop

Develop

Author: mehmetpekdemir

src/com/mehmetpekdemir/Main.java

@@ -1,6 +1,7 @@
 package com.mehmetpekdemir;
 
 import java.util.PriorityQueue;
+import java.util.TreeSet;
 
 import com.mehmetpekdemir.list.doublylinkedlist.EmployeeDoublyLinkedList;
 import com.mehmetpekdemir.list.singlylinkedlist.EmployeeLinkedList;
@@ -220,6 +221,33 @@ public static void main(String[] args) {
 		System.out.println(tree.min());
 		System.out.println(tree.max());
 
+		tree.delete(30);
+		tree.traverseInOrder();
+
+		System.out.println("\n----------TreeSet----------");
+
+		TreeSet<Employee> treeSet = new TreeSet<Employee>();
+		treeSet.add(new Employee(1L, "Mehmet", "Pekdemir"));
+		treeSet.add(new Employee(2L, "Mehmet2", "Pekdemir2"));
+		treeSet.add(new Employee(3L, "Mehmet3", "Pekdemir3"));
+
+		// Duplicates will not get insert
+		treeSet.add(new Employee(3L, "Mehmet3", "Pekdemir3"));
+
+		treeSet.forEach(System.out::println);
+
+		System.out.println("\n----------TreeSet String----------");
+		TreeSet<String> treeSetString = new TreeSet<String>();
+
+		treeSetString.add("Mehmet");
+		treeSetString.add("Pekdemir");
+		treeSetString.add("Test");
+		treeSetString.add("A");
+		treeSetString.add("B");
+		treeSetString.add("C");
+
+		treeSetString.forEach(System.out::println);
+
 	}
 
 }

src/com/mehmetpekdemir/tree/Tree.java

@@ -42,21 +42,55 @@ public TreeNode get(int value) {
 
 		return null;
 	}
-	
+
 	public int min() {
-		if(root == null) {
+		if (root == null) {
 			return Integer.MIN_VALUE;
 		} else {
 			return root.min();
 		}
 	}
-	
+
 	public int max() {
-		if(root == null) {
+		if (root == null) {
 			return Integer.MAX_VALUE;
 		} else {
 			return root.max();
 		}
 	}
 
+	public void delete(int value) {
+		root = delete(root, value);
+	}
+
+	private TreeNode delete(TreeNode subTreeRoot, int value) {
+		if (subTreeRoot == null) {
+			return subTreeRoot;
+		}
+
+		if (value < subTreeRoot.getData()) {
+			subTreeRoot.setLeftChild(delete(subTreeRoot.getLeftChild(), value));
+		} else if (value > subTreeRoot.getData()) {
+			subTreeRoot.setRightChild(delete(subTreeRoot.getRightChild(), value));
+		} else {
+			// Cases 1 and 2 : Node to delete has 0 or 1 child
+			if (subTreeRoot.getLeftChild() == null) {
+				return subTreeRoot.getRightChild();
+			} else if (subTreeRoot.getRightChild() == null) {
+				return subTreeRoot.getLeftChild();
+			}
+			// Case 3 : Node to delete has 2 children
+
+			// Replace the value in the subTreeRoot node with the smallest value
+			// from the right subtree
+			subTreeRoot.setData(subTreeRoot.getRightChild().min());
+
+			// Delete the node that has the smallest value in the right subtree
+			subTreeRoot.setRightChild(delete(subTreeRoot.getRightChild(), subTreeRoot.getData()));
+
+		}
+
+		return subTreeRoot;
+	}
+
 }