some exercises

1 files changed, 11 insertions, 0 deletions

diff --git a/coding-exercises/2/31.rkt b/coding-exercises/2/31.rkt
new file mode 100644
index 0000000..08e0d51
--- /dev/null
+++ b/coding-exercises/2/31.rkt
@@ -0,0 +1,11 @@
+#lang racket
+(define (tree-map fn tree)
+  (map (lambda (subtree)
+         (if (pair? subtree)
+           (tree-map fn subtree)
+           (fn subtree)))
+       tree))
+  
+(define test-tree (list 1 (list 2 (list 3 4) 5) (list 6 7)))
+((lambda ()
+   (display (tree-map (lambda (x) (* x x)) test-tree))))