Recursive Tree Traversals

Preorder Traversal :

void preorderTraversal(struct Node *ptr) {

    if (ptr != NULL) {
        printf("%d\t", ptr -> data);
        preorderTraversal(ptr -> left);
        preorderTraversal(ptr -> right);
    }

}

Inorder Traversal :

void inorderTraversal(struct Node *ptr) {

    if (ptr != NULL) {
        inorderTraversal(ptr -> left);
        printf("%d\t", ptr -> data);
        inorderTraversal(ptr -> right);
    }

}

Postorder Traversal :

void postorderTraversal(struct Node *ptr) {

    if (ptr != NULL) {
        postorderTraversal(ptr -> left);
        postorderTraversal(ptr -> right);
        printf("%d\t", ptr -> data);
    }

}

The time complexity of all 3 traversal methods in O(n).

Contributed by Nitin Ranganath