Question

我已完成下面的代码，（尚未完成数字和错误扫描部分），但测试结果告诉我存在内存错误。我不知道怎么回事......

这是我的代码：

class lexicon(object):

def __init__(self):
    pass

def scan(self, sentence):

    direction = ["north", "south", "east", "west", "dwon", "up", "left", "right", "back"]
    verb = ["go", "stop", "kill", "eat"]
    stop = ["the", "in", "of", "from", "at", "it"]
    noun = ["door", "bear", "princess", "cabinet"]
    word_type = [direction, verb, stop, noun]

    wordlist = sentence.split()
    result = []

    for a in wordlist:
        x = 0
        c = 0
        while x < len(word_type) and c == 0:
            b = word_type[x]

            if a not in b:
                x += 1
            else:
                result.append((b,a))
                c == 1

        if x == len(word_type):
            result.append(("error",a))

    return result

这是test_lexicon：

from nose.tools import *
from game48 import lexicon

def test_directions():
    lexicon1 = lexicon()
    assert_equal(lexicon1.scan("north"),[("direction","north")])
    result = lexicon.scan("notrh south east")
    assert_equal(result, [("direction", "north"), ("direction", "south"), ("direction", "east")])

这就是结果：

ERROR: tests.lexicon_tests.test_directions
----------------------------------------------------------------------
Traceback (most recent call last):
  File "c:\users\sine\appdata\local\programs\python\python35-32\lib\site-packages\nose\case.py", line 198, in runTest
    self.test(*self.arg)
  File "E:\Python\exercises of learn python the hard way\ex48\tests\lexicon_tests.py", line 6, in test_directions
    assert_equal(lexicon1.scan("north"),[("direction","north")])
  File "E:\Python\exercises of learn python the hard way\ex48\game48.py", line 26, in scan
    result.append((b,a))
MemoryError

======================================================================
ERROR: tests.lexicon_tests.test_verbs

Answer 1

        else:
            result.append((b,a))
            c == 1

在这种情况下c和x都没有改变，因此循环while x < len(word_type) and c == 0:一直在运行和运行，result无限增长并消耗掉所有内存。

我不确定您是想要c = 1还是c += 1，但它不太可能是c == 1因为它是无操作。你没有利用相等比较的结果。

Answer 2

你可能想让c = 1，而不是c == 1。在这种情况下，没有什么会改变，你将有无限循环。

Answer 3

除了循环问题之外，还有另一个问题，lexicon1.scan("north")将最终返回：

[(["north", "south", "east", "west", "dwon", "up", "left", "right", "back"], "north")]

代替所需的：[('direction', 'north')]

我们可以解决这个问题，并简化代码，使用字典来保存单词：

class lexicon(object):

    def __init__(self):
        self.word_types = {
            "direction": ["north", "south", "east", "west", "down", "up", "left", "right", "back"],
            "verb": ["go", "stop", "kill", "eat"],
            "stop": ["the", "in", "of", "from", "at", "it"],
            "noun": ["door", "bear", "princess", "cabinet"]
        }

    def scan(self, sentence):
        wordlist = sentence.split()
        result = []

        for word in wordlist:
            for word_type in self.word_types:
                if word in self.word_types[word_type]:
                    result.append((word_type, word))
                    break
            else:
                result.append(("error", word))

        return result

请注意，else循环上的for与else语句中的if不同，可以认为它意味着“没有中断”，即如果永远不会达到break语句并且循环用完就要执行的代码。

学习python艰难的方式ex48 [内存错误]

3 个答案: