乱数を生成する
gosh> (use srfi-27) #<undef> gosh> (random-integer 5) 4 gosh> (random-integer 5) 0 gosh> (map random-integer '(5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5)) (4 4 0 4 4 1 3 1 0 2 1 0 2 4 4 4 4 4 0 3)
take*とdrop* (寛容♡)
gosh> (define (make-heart i) (string-append "h" (number->string i))) make-heart gosh> (define cards (map make-heart (iota 13 1 1))) cards gosh> cards ("h1" "h2" "h3" "h4" "h5" "h6" "h7" "h8" "h9" "h10" "h11" "h12" "h13") gosh> (use util.list) #<undef> gosh> (take* cards 3) ("h1" "h2" "h3") gosh> (drop* cards 3) ("h4" "h5" "h6" "h7" "h8" "h9" "h10" "h11" "h12" "h13")
リストxからn番目の要素を除いたリストを返す関数
gosh> (define (remains x n) (if (= (length x) 1) x (append (take* x n) (drop* x (+ n 1)))) ) remains gosh> (remains cards 2) ("h1" "h2" "h4" "h5" "h6" "h7" "h8" "h9" "h10" "h11" "h12" "h13") gosh> (remains cards 0) ("h2" "h3" "h4" "h5" "h6" "h7" "h8" "h9" "h10" "h11" "h12" "h13") gosh> (remains cards 12) ("h1" "h2" "h3" "h4" "h5" "h6" "h7" "h8" "h9" "h10" "h11" "h12")
リストxをシャッフルしたリストを返す関数
gosh> (define (shuffle x) (let ((n (random-integer (length x)))) (if (= (length x) 1) x (append (list (ref x n)) (shuffle (remains x n))))) ) shuffle gosh> (shuffle cards) ("h3" "h8" "h13" "h12" "h11" "h10" "h9" "h1" "h6" "h7" "h5" "h4" "h2") gosh> (shuffle cards) ("h2" "h7" "h11" "h12" "h4" "h3" "h1" "h8" "h5" "h13" "h9" "h10" "h6")
