Python-文字游戏 "Ghost"、文件 I/O 和列表问题

Question

我想为文字游戏创建计算机 Ghost 。然而，我在思考一种处理访问庞大单词列表的好方法时遇到了问题。这是我当前的实现(不起作用):

import os, random, sys, math, string


def main():

    #Contains a huge wordlist-- opened up for reading
    dictionary = open("wordlist.txt", "r")
    wordlist = []
    win= 0
    turn= 0
    firstrun = 0
    word = ""

    #while nobody has won the game
    while win==0:
        if turn == 0:
            #get first letter from input
            foo = raw_input("Choose a letter: ")[0]
            word+=foo
            print "**Current word**: "+ word
            #Computer's turn
            turn = 1
        if turn == 1:
            #During the first run the program gets all definitively 
            #winning words (words that have odd-number lengths)
            #from the "dictionary" file and puts them in a list
            if firstrun== 0:
                for line in dictionary:
                    #if the line in the dictionary starts with the current 
                    #word and has an odd-number of letters                                                                                                
                    if str(line).startswith(word) and len(line)%2 == 0:
                        wordlist.append(line[0: len(line)-1])
                print "first run complete... size = "+str(len(wordlist))
                firstrun = 1
            else:   #This is run after the second computer move         
                for line in wordlist:
                    #THIS DOES NOT WORK-- THIS IS THE PROBLEM.
                    #I want it to remove from the list every single
                    #word that does not conform to the current limitations
                    #of the "word" variable. 
                    if not line.startswith(word): 
                        wordlist.remove(line)
                print "removal complete... size = "+str(len(wordlist))

            turn = 0




if __name__ == "__main__":
    main()

我已经在代码中划定了问题区域。我不知道为什么它不起作用。应该发生什么:假设列表中填充了所有以“a”开头的单词。然后用户选择字母“b”。目标单词必须以“ab”开头。应该发生的情况是，列表中所有未直接跟在“b”后面的“a”单词都应该被删除。

如果有人能让我知道一种更有效的方法来做到这一点，然后制作一个巨大的初始列表，我也将不胜感激。

Answer 1

我建议不要从列表中删除单词。它会非常慢，因为删除列表中间的时间复杂度为 O(N)。

最好只是制作一个新列表。一种可能的方法是更换线路

for line in wordlist:
    if not line.startswith(word):
        wordlist.remove(line)

与

wordlist = [w for w in wordlist if w.startswith(word)]