Postorder traversal

Postorder traversal: In postorder traversal root is visited at the last.

 Steps:

 1. Traverse the left subtree
2. Traverse the right subtree
3. Visit the root

 Code:

void postOrder(Node root) {
    if(root==null)
        return;
    postOrder(root.left);
    postOrder(root.right);
    System.out.print(root.data+" ");

}


Illustration:






Postorder traversal of given tree is 2, 4, 5, 3, 1










Traverse the left subtree





 Traverse the right subtree





 Traverse the left subtree





 Traverse the right subtree





 Visit the root





 Visit the root ( since we finished traversing left and right subtrees of 7 )



















































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