From: jim Date: Wed, 4 Mar 2015 19:44:51 +0000 (-0500) Subject: add hint for tree enumeration X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?p=lambda.git;a=commitdiff_plain;h=3b82c6f6da5e92a42e99b6afd2c5b7e4d6a75f67 add hint for tree enumeration --- diff --git a/exercises/assignment5.mdwn b/exercises/assignment5.mdwn index 7765a7e7..0494fa7d 100644 --- a/exercises/assignment5.mdwn +++ b/exercises/assignment5.mdwn @@ -116,7 +116,7 @@ Choose one of these languages and write the following functions. 6. How would you use the function defined in problem 4 to enumerate a tree's fringe? (Don't worry about whether it comes out left-to-right or right-to-left.) -7. Write a recursive function to make a copy of a `color_tree` with the same structure and inner branch colors, but where the leftmost leaf is now labeled `0`, the second-leftmost leaf is now labeled `1`, and so on. +7. Write a recursive function to make a copy of a `color_tree` with the same structure and inner branch colors, but where the leftmost leaf is now labeled `0`, the second-leftmost leaf is now labeled `1`, and so on. (Here's a [[hint|assignment5 hint3]], if you need one.) 8. (More challenging.) Write a recursive function that makes a copy of a `color_tree` with the same structure and inner branch colors, but replaces each leaf label with the `int` that reports how many of that leaf's ancestors are labeled `Red`. For example, if we give your function a tree: