---
title: 拡張FizzBuzz (CommonLisp版)
tags: []
categories: ["Programming", "Lisp", "CommonLisp"]
date: 2010-02-24T17:37:43Z
updated: 2010-02-25T23:33:18Z
---

<p>
<a href="http://ik.am/blog/2009/12/06/%e6%8b%a1%e5%bc%b5fizzbuzz/">ここ</a>からの編集して転載。
</p>
<p>
<a href="http://ja.wikipedia.org/wiki/Fizz_Buzz">FizzBuzz</a>の拡張で、3、5以外にも増えたらどうする？
</p>
<h3>拡張FizzBuzz定義マクロ</h3>
<pre class="prettyprint lang-cl">
(defmacro define-fizzbuzz (fizz-buzz-list)
  `(defun ,(read-from-string (format nil "~{~a~^-~}" (mapcar #'cdr fizz-buzz-list))) (x)
     (format nil "~{~a~^~}"
             (nconc ,@(loop for i in fizz-buzz-list collect `(if (zerop (mod x ,(car i))) (list ',(cdr i))))))
     )
  )
;; 使い方
(define-fizzbuzz ((3 . fizz) (5 . buzz))) ; fizz-buzz
(define-fizzbuzz ((3 . fizz) (5 . buzz) (7 . foo))) ; fizz-buzz-foo
(define-fizzbuzz ((3 . fizz) (5 . buzz) (7 . foo) (11 . bar))) ; fizz-buzz-foo-bar
</pre>
<p>
展開すると、
</p>
<pre class="prettyprint lang-cl">
CL-USER> (macroexpand-1 '(define-fizzbuzz ((3 . fizz) (5 . buzz))))
(DEFUN FIZZ-BUZZ (X)
  (FORMAT NIL "~{~a~^~}"
          (NCONC (IF (ZEROP (MOD X 3)) (LIST 'FIZZ))
                 (IF (ZEROP (MOD X 5)) (LIST 'BUZZ)))))
T
CL-USER> (macroexpand-1 '(define-fizzbuzz ((3 . fizz) (5 . buzz) (7 . foo))))
(DEFUN FIZZ-BUZZ-FOO (X)
  (FORMAT NIL "~{~a~^~}"
          (NCONC (IF (ZEROP (MOD X 3)) (LIST 'FIZZ))
                 (IF (ZEROP (MOD X 5)) (LIST 'BUZZ))
                 (IF (ZEROP (MOD X 7)) (LIST 'FOO)))))
T
CL-USER> (macroexpand-1 '(define-fizzbuzz ((3 . fizz) (5 . buzz) (7 . foo) (11 . bar))))
(DEFUN FIZZ-BUZZ-FOO-BAR (X)
  (FORMAT NIL "~{~a~^~}"
          (NCONC (IF (ZEROP (MOD X 3)) (LIST 'FIZZ))
                 (IF (ZEROP (MOD X 5)) (LIST 'BUZZ))
                 (IF (ZEROP (MOD X 7)) (LIST 'FOO))
                 (IF (ZEROP (MOD X 11)) (LIST 'BAR)))))
T
</pre>
<p>
一応、実行結果（fizz-buzz-fooのみ）。
</p>
<pre class="prettyprint lang-cl">
CL-USER> (loop for i from 1 to 105 do (format t "~a -> ~a~%" i (fizz-buzz-foo i)))
1 -> 1
2 -> 2
3 -> FIZZ
4 -> 4
5 -> BUZZ
6 -> FIZZ
7 -> FOO
8 -> 8
9 -> FIZZ
10 -> BUZZ
11 -> 11
12 -> FIZZ
13 -> 13
14 -> FOO
15 -> FIZZBUZZ
16 -> 16
17 -> 17
18 -> FIZZ
19 -> 19
20 -> BUZZ
21 -> FIZZFOO
22 -> 22
23 -> 23
24 -> FIZZ
25 -> BUZZ
26 -> 26
27 -> FIZZ
28 -> FOO
29 -> 29
30 -> FIZZBUZZ
31 -> 31
32 -> 32
33 -> FIZZ
34 -> 34
35 -> BUZZFOO
36 -> FIZZ
37 -> 37
38 -> 38
39 -> FIZZ
40 -> BUZZ
41 -> 41
42 -> FIZZFOO
43 -> 43
44 -> 44
45 -> FIZZBUZZ
46 -> 46
47 -> 47
48 -> FIZZ
49 -> FOO
50 -> BUZZ
51 -> FIZZ
52 -> 52
53 -> 53
54 -> FIZZ
55 -> BUZZ
56 -> FOO
57 -> FIZZ
58 -> 58
59 -> 59
60 -> FIZZBUZZ
61 -> 61
62 -> 62
63 -> FIZZFOO
64 -> 64
65 -> BUZZ
66 -> FIZZ
67 -> 67
68 -> 68
69 -> FIZZ
70 -> BUZZFOO
71 -> 71
72 -> FIZZ
73 -> 73
74 -> 74
75 -> FIZZBUZZ
76 -> 76
77 -> FOO
78 -> FIZZ
79 -> 79
80 -> BUZZ
81 -> FIZZ
82 -> 82
83 -> 83
84 -> FIZZFOO
85 -> BUZZ
86 -> 86
87 -> FIZZ
88 -> 88
89 -> 89
90 -> FIZZBUZZ
91 -> FOO
92 -> 92
93 -> FIZZ
94 -> 94
95 -> BUZZ
96 -> FIZZ
97 -> 97
98 -> FOO
99 -> FIZZ
100 -> BUZZ
101 -> 101
102 -> FIZZ
103 -> 103
104 -> 104
105 -> FIZZBUZZFOO
</pre>