Create postorder.cpp

CPP/Trees/postorder.cpp

@@ -0,0 +1,52 @@
+// C++ program for different tree traversals
+#include <bits/stdc++.h>
+using namespace std;
+
+/* A binary tree node has data, pointer to left child
+and a pointer to right child */
+struct Node {
+	int data;
+	struct Node *left, *right;
+};
+
+// Utility function to create a new tree node
+Node* newNode(int data)
+{
+	Node* temp = new Node;
+	temp->data = data;
+	temp->left = temp->right = NULL;
+	return temp;
+}
+
+/* Given a binary tree, print its nodes according to the
+"bottom-up" postorder traversal. */
+void printPostorder(struct 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
+	cout << node->data << " ";
+}
+
+/* Driver code*/
+int main()
+{
+	struct Node* root = newNode(1);
+	root->left = newNode(2);
+	root->right = newNode(3);
+	root->left->left = newNode(4);
+	root->left->right = newNode(5);
+
+	// Function call
+	cout << "\nPostorder traversal of binary tree is \n";
+	printPostorder(root);
+
+	return 0;
+}