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1 files changed, 20 insertions, 0 deletions

diff --git a/coding-exercises/2/64.rkt b/coding-exercises/2/64.rkt
new file mode 100644
index 0000000..90994e8
--- /dev/null
+++ b/coding-exercises/2/64.rkt
@@ -0,0 +1,20 @@
+#lang racket
+(define (list->tree elements)
+  (car (partial-tree elements (length elements))))
+
+(define (partial-tree elts n)
+  (if (= n 0)
+    (let ((left-size (quotient (- n 1)
+                               2)))
+      (let ((left-result (partial-tree elts left-size)))
+        (let ((left-tree (car left-result))
+              (non-left-elts (cdr left-result))
+              (right-size (- n (+ left-size 1))))
+              
+          (let ((this-entry (car non-left-elts))
+                (right-result (partial-tree (cdr non-left-elts)
+                                            right-size)))
+            (let ((right-tree (car right-result))
+                  (remaining-elts (cdr right-result)))
+              (cons (make-tree thientry left-tree right-tree)
+                    remaining-elts))))))))