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+#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))))))))