tree traversal in java

Author: jbhavya11

tree-traversal.java

@@ -0,0 +1,100 @@
+// Java program for different tree traversals 
+
+/* Class containing left and right child of current 
+node and key value*/
+class Node 
+{ 
+	int key; 
+	Node left, right; 
+
+	public Node(int item) 
+	{ 
+		key = item; 
+		left = right = null; 
+	} 
+} 
+
+class BinaryTree 
+{ 
+	// Root of Binary Tree 
+	Node root; 
+
+	BinaryTree() 
+	{ 
+		root = null; 
+	} 
+
+	/* Given a binary tree, print its nodes according to the 
+	"bottom-up" postorder traversal. */
+	void printPostorder(Node node) 
+	{ 
+		if (node == null) 
+			return; 
+
+		// first recur on left subtree 
+		printPostorder(node.left); 
+
+		// then recur on right subtree 
+		printPostorder(node.right); 
+
+		// now deal with the node 
+		System.out.print(node.key + " "); 
+	} 
+
+	/* Given a binary tree, print its nodes in inorder*/
+	void printInorder(Node node) 
+	{ 
+		if (node == null) 
+			return; 
+
+		/* first recur on left child */
+		printInorder(node.left); 
+
+		/* then print the data of node */
+		System.out.print(node.key + " "); 
+
+		/* now recur on right child */
+		printInorder(node.right); 
+	} 
+
+	/* Given a binary tree, print its nodes in preorder*/
+	void printPreorder(Node node) 
+	{ 
+		if (node == null) 
+			return; 
+
+		/* first print data of node */
+		System.out.print(node.key + " "); 
+
+		/* then recur on left sutree */
+		printPreorder(node.left); 
+
+		/* now recur on right subtree */
+		printPreorder(node.right); 
+	} 
+
+	// Wrappers over above recursive functions 
+	void printPostorder() {	 printPostorder(root); } 
+	void printInorder() {	 printInorder(root); } 
+	void printPreorder() {	 printPreorder(root); } 
+
+	// Driver method 
+	public static void main(String[] args) 
+	{ 
+		BinaryTree tree = new BinaryTree(); 
+		tree.root = new Node(1); 
+		tree.root.left = new Node(2); 
+		tree.root.right = new Node(3); 
+		tree.root.left.left = new Node(4); 
+		tree.root.left.right = new Node(5); 
+
+		System.out.println("Preorder traversal of binary tree is "); 
+		tree.printPreorder(); 
+
+		System.out.println("\nInorder traversal of binary tree is "); 
+		tree.printInorder(); 
+
+		System.out.println("\nPostorder traversal of binary tree is "); 
+		tree.printPostorder(); 
+	} 
+}