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+#lang scheme
+
+; ------------------------------------------------------------
+; PROGRAM NAME: HW02.rkt
+;
+; DESCRIPTION: Second homework assignment for CSI310
+;
+; AUTHOR: Ben Burwell ; CS 310: Theory of Programming Languages
+; Muhlenberg College
+;
+
+;; ---------
+;; NAME: invert
+;; DESC: takes a list of 2-lists (lists of length 2), and returns a list with each 2-list reversed.
+
+(define invert
+  (lambda (l)
+    (map swap l)))
+
+(define swap
+  (lambda (l)
+    (if (= 2 (length l))
+     (list (cadr l) (car l))
+     (display "Error"))))
+
+;; TEST
+(invert '((2 1) (4 3) (6 5))) ;; should return (1 2) (3 4) (5 6)
+
+
+;; ---------
+;; NAME: compose23
+;; DESC: that takes 1, 2, or 3 procedures and composes them, as specified by the equation:
+;;           (compose f g h) = (compose f (compose g h))
+
+(define compose23
+  (lambda funcs
+    (if (= (length funcs) 1)
+     (car funcs)
+     (if (= (length funcs) 2)
+         ((car funcs) (cadr funcs))
+         (if (= (length funcs) 3)
+         ((car funcs (cadr funcs) (caddr funcs))))))))
+\ No newline at end of file