Python - Lists(reverse pairs)

Think Python

開発環境

• OS X El Capitan - Apple (OS)
• Emacs (Text Editor)
• Python 3.5 (プログラミング言語)

Think Python (Allen B. Downey (著)、 O'Reilly Media)のChapter 10.(Lists)のExercises 10-11.(No. 2386)を取り組んでみる。

Exercises 10-11.(No. 2386)

コード(Emacs)

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import math
import time
import random
import bisect


def words2list(filename):
    out = []
    with open(filename) as f:
        for word in f:
            word = word.strip()
            out.append(word)
    return out


def in_bisect(elems, val):
    l = len(elems)
    i = bisect.bisect_left(elems, val)
    if i != l and elems[i] == val:
        return i
    return None

if __name__ == '__main__':
    filename = 'words.txt'
    words = words2list(filename)
    words.sort()
    n = len(words)
    l = []
    for i, word in enumerate(words):
        reversed_word = word[::-1]
        j = in_bisect(words, reversed_word)
        if not j is None:
            l.append((word, reversed_word))
    for pair in l[:10] + l[-10:]:
        print(pair)

入出力結果(Terminal, IPython)

$ ./sample11.py
('aa', 'aa')
('aba', 'aba')
('abut', 'tuba')
('ad', 'da')
('ados', 'soda')
('aga', 'aga')
('agar', 'raga')
('agas', 'saga')
('agenes', 'senega')
('ah', 'ha')
('yak', 'kay')
('yam', 'may')
('yap', 'pay')
('yaps', 'spay')
('yar', 'ray')
('yard', 'dray')
('yaw', 'way')
('yaws', 'sway')
('yay', 'yay')
('yeh', 'hey')
$