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diff --git a/src/scheme/test/hanoi.scheme b/src/scheme/test/hanoi.scheme
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+;
+; Towers of Hanoi
+;
+; Copyright © 2016 Keith Packard <keithp@keithp.com>
+;
+; This program is free software; you can redistribute it and/or modify
+; it under the terms of the GNU General Public License as published by
+; the Free Software Foundation, either version 2 of the License, or
+; (at your option) any later version.
+;
+; This program is distributed in the hope that it will be useful, but
+; WITHOUT ANY WARRANTY; without even the implied warranty of
+; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+; General Public License for more details.
+;
+
+					; ANSI control sequences
+
+(define (move-to col row)
+  (for-each display (list "\033[" row ";" col "H"))
+  )
+
+(define (clear)
+  (display "\033[2J")
+  )
+
+(define (display-string x y str)
+  (move-to x y)
+  (display str)
+  )
+
+(define (make-piece num max)
+					; A piece for position 'num'
+					; is num + 1 + num stars
+					; centered in a field of max *
+					; 2 + 1 characters with spaces
+					; on either side. This way,
+					; every piece is the same
+					; number of characters
+
+  (define (chars n c)
+    (if (zero? n) ""
+      (+ c (chars (- n 1) c))
+      )
+    )
+  (+ (chars (- max num 1) " ")
+     (chars (+ (* num 2) 1) "*")
+     (chars (- max num 1) " ")
+     )
+  )
+
+(define (make-pieces max)
+					; Make a list of numbers from 0 to max-1
+  (define (nums cur max)
+    (if (= cur max) ()
+      (cons cur (nums (+ cur 1) max))
+      )
+    )
+					; Create a list of pieces
+
+  (map (lambda (x) (make-piece x max)) (nums 0 max))
+  )
+
+					; Here's all of the towers of pieces
+					; This is generated when the program is run
+
+(define towers ())
+
+					; position of the bottom of
+					; the stacks set at runtime
+(define bottom-y 0)
+(define left-x 0)
+
+(define move-delay 25)
+
+					; Display one tower, clearing any
+					; space above it
+
+(define (display-tower x y clear tower)
+  (cond ((= 0 clear)
+	 (cond ((not (null? tower))
+		(display-string x y (car tower))
+		(display-tower x (+ y 1) 0 (cdr tower))
+		)
+	       )
+	 )
+	(else 
+	 (display-string x y "                    ")
+	 (display-tower x (+ y 1) (- clear 1) tower)
+	 )
+	)
+  )
+
+					; Position of the top of the tower on the screen
+					; Shorter towers start further down the screen
+
+(define (tower-pos tower)
+  (- bottom-y (length tower))
+  )
+
+					; Display all of the towers, spaced 20 columns apart
+
+(define (display-towers x towers)
+  (cond ((not (null? towers))
+	 (display-tower x 0 (tower-pos (car towers)) (car towers))
+	 (display-towers (+ x 20) (cdr towers)))
+	)
+  )
+
+					; Display all of the towers, then move the cursor
+					; out of the way and flush the output
+
+(define (display-hanoi)
+  (display-towers left-x towers)
+  (move-to 1 23)
+  (flush-output)
+  (delay move-delay)
+  )
+
+					; Reset towers to the starting state, with
+					; all of the pieces in the first tower and the
+					; other two empty
+
+(define (reset-towers len)
+  (set! towers (list (make-pieces len) () ()))
+  (set! bottom-y (+ len 3))
+  )
+
+					; Move a piece from the top of one tower
+					; to the top of another
+
+(define (move-piece from to)
+
+					; references to the cons holding the two towers
+
+  (define from-tower (list-tail towers from))
+  (define to-tower (list-tail towers to))
+
+					; stick the car of from-tower onto to-tower
+
+  (set-car! to-tower (cons (caar from-tower) (car to-tower)))
+
+					; remove the car of from-tower
+
+  (set-car! from-tower (cdar from-tower))
+  )
+
+					; The implementation of the game
+
+(define (_hanoi n from to use)
+  (cond ((= 1 n)
+	 (move-piece from to)
+	 (display-hanoi)
+	 )
+	(else
+	 (_hanoi (- n 1) from use to)
+	 (_hanoi 1 from to use)
+	 (_hanoi (- n 1) use to from)
+	 )
+	)
+  )
+
+					; A pretty interface which
+					; resets the state of the game,
+					; clears the screen and runs
+					; the program
+
+(define (hanoi len)
+  (reset-towers len)
+  (clear)
+  (display-hanoi)
+  (_hanoi len 0 1 2)
+  #t
+  )