Question

for a programming assignment, I have to load a tree into an array in order.

The recursive algorithm itself is no problem for me. The problem I’m having is keeping the subscript/element numbers increased periodically so that the data goes into the right array element, instead of overwriting each other after calls return.

void foo( currentNode, data[], element? )
{
    // base case
    if ( currentNode == NULL )

    foo( currentNode->left, data, element? );
    data[ element++ ] = currentNode->data; // what do I do in between the left and right subtree calls?
    foo( currentNode->right, data, element? );
}

So, how do I increase the element so that it only increases to the next spot of the array for an inorder traversal?

Hints are nice, but I wouldn’t mind solutions.

Answer 1

Make your data parameter a reference to a pointer:

void foo(Node* currentNode, ContentType*& data) {
  //...
  *data++ = currentNode->data;
  //..
}