User talk:Elanor988

Welcome!
Hello, Elanor988, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are a few links to pages you might find helpful:


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Please remember to sign your messages on talk pages by typing four tildes ( ~ ); this will automatically insert your username and the date. If you need help, check out Questions, ask me on my talk page, or, and a volunteer should respond shortly. Again, welcome! CiaPan (talk) 07:42, 29 January 2020 (UTC)

Test
Thank you for experimenting with the page Binary tree on Wikipedia as you did with this edit. Your test worked, and it has been reverted or removed. Please use the sandbox for any other tests you may want to do. Take a look at the welcome page to learn more about contributing to our encyclopedia. --CiaPan (talk) 07:43, 29 January 2020 (UTC)

Empty links in binary trees
In your edit Special:Diff/938020709 to the article Binary tree you replaced a number of free links (empty pointers to non-existent nodes) from $n+1$ to $n–1$. Please note the empty tree contains zero nodes and one empty pointer to the non-existent root node. If the empty tree is too weird to consider, let's start from $n=1$: a single-node tree has one node and two empty links (from the only node, which has no children). So it holds for empty and one-node trees that $N_{empty} = n+1$. Whenever you add a next node to a tree, the node uses one of empty links and adds itself two empty links. This way a net change in empty links number is $–1+2 = +1$ and a change in nodes number is $+1$, hence the initial correlation $N_{empty} = n+1$ is preserved. Doesn't matter if the tree is full, perfect, balanced or degenerate, as long as it is a binary tree the number of empty links equals the number of nodes plus one. --CiaPan (talk) 07:43, 29 January 2020 (UTC)