euler tour/traversal anyone please?

[devilclaw]

does anyone have an idea how the code looks like when traversing a binary tree in euler's tour??

[arpsmack]

? I'm confused. Euler tours only exist in connected graphs where each node has an even degree. This isn't the case in most binary trees....

[devilclaw]

i have read that there's a euler's traversal for binary... the preorder, inorder, and postorder traversals are special cases of the Euler tour traversal. however i really don't know how it traverses a binary tree..

[arpsmack]

Oh ok, well if you're just looking for the different traversals of a binary tree, they can be easily expressed recursively:

void traverse_in_order(Node * n) {
   if (n->left_child != NULL)
      traverse_in_order(n->left_child);
   
   printf("%d\n", n->value);

   if (n->right_child != NULL)
      traverse_in_order(n->right_child);
}

You would pass this function a pointer to the root node of your tree. To do preorder and postorder traversals, you just change the order in which you do things.

For example, for a preorder traversal, you would first print the value, then do left, and then right child.