2018年12月14日金曜日

開発環境

問題解決のPythonプログラミング ―数学パズルで鍛えるアルゴリズム的思考 (Srini Devadas (著)、黒川 利明 (翻訳)、オライリージャパン)の12章(ひねりを加えたバラモンの塔)、練習問題(パズル問題1)を取り組んでみる。

コード(Emacs)

Python 3

#!/usr/bin/env python3


def hanoi(ring_number: int, origin: int,
          peg1: int, peg2: int, peg3: int) -> int:
    num_moves = 0
    if ring_number > 0:
        num_moves += hanoi(ring_number - 1, origin, peg1, peg3, peg2)
        print(
            f'Move ring {ring_number + origin} from peg {peg1} to peg {peg3}')
        num_moves += 1
        num_moves += hanoi(ring_number - 1, origin, peg2, peg1, peg3)
    return num_moves


def hanoi_four_peg(ring_number: int,
                   peg1: int, peg2: int, peg3: int, peg4: int) -> int:
    num_moves = 0
    if ring_number > 0:
        num_moves += hanoi(ring_number // 2, 0, peg1, peg2, peg4)
        origin = ring_number // 2
        num_moves += hanoi(ring_number // 2, origin, peg1, peg2, peg3)
        num_moves += hanoi(ring_number // 2, 0, peg4, peg1, peg3)
    return num_moves


if __name__ == '__main__':
    num = hanoi_four_peg(8, 1, 2, 3, 4)
    print(num, num == 45)

入出力結果(Terminal, cmd(コマンドプロンプト), Jupyter(IPython))

$ ./sample1.py
Move ring 1 from peg 1 to peg 2
Move ring 2 from peg 1 to peg 4
Move ring 1 from peg 2 to peg 4
Move ring 3 from peg 1 to peg 2
Move ring 1 from peg 4 to peg 1
Move ring 2 from peg 4 to peg 2
Move ring 1 from peg 1 to peg 2
Move ring 4 from peg 1 to peg 4
Move ring 1 from peg 2 to peg 4
Move ring 2 from peg 2 to peg 1
Move ring 1 from peg 4 to peg 1
Move ring 3 from peg 2 to peg 4
Move ring 1 from peg 1 to peg 2
Move ring 2 from peg 1 to peg 4
Move ring 1 from peg 2 to peg 4
Move ring 5 from peg 1 to peg 2
Move ring 6 from peg 1 to peg 3
Move ring 5 from peg 2 to peg 3
Move ring 7 from peg 1 to peg 2
Move ring 5 from peg 3 to peg 1
Move ring 6 from peg 3 to peg 2
Move ring 5 from peg 1 to peg 2
Move ring 8 from peg 1 to peg 3
Move ring 5 from peg 2 to peg 3
Move ring 6 from peg 2 to peg 1
Move ring 5 from peg 3 to peg 1
Move ring 7 from peg 2 to peg 3
Move ring 5 from peg 1 to peg 2
Move ring 6 from peg 1 to peg 3
Move ring 5 from peg 2 to peg 3
Move ring 1 from peg 4 to peg 1
Move ring 2 from peg 4 to peg 3
Move ring 1 from peg 1 to peg 3
Move ring 3 from peg 4 to peg 1
Move ring 1 from peg 3 to peg 4
Move ring 2 from peg 3 to peg 1
Move ring 1 from peg 4 to peg 1
Move ring 4 from peg 4 to peg 3
Move ring 1 from peg 1 to peg 3
Move ring 2 from peg 1 to peg 4
Move ring 1 from peg 3 to peg 4
Move ring 3 from peg 1 to peg 3
Move ring 1 from peg 4 to peg 1
Move ring 2 from peg 4 to peg 3
Move ring 1 from peg 1 to peg 3
45 True
$

0 コメント:

コメントを投稿

関連コンテンツ