任务详情
给定一段英文句子，判断句中单词拼写是否满足以下规则。
除以下特殊情况外，句子中第一个单词首字母必须大写，其它所有单词小写：
任务要求
输入英文句子为 str 类型，输出为 bool 类型；
如果句子满足规则要求，程序返回结果为 True；否则返回 False。
测试用例
输入：'I love Python' 输出：True
输入：'python love me' 输出：False
输入： 'JUST DO IT' 输出：True
输入： 'I come from HK' 输出：True
输入： 'Machinelearning is so hot' 输出：False
输入： 'I love Python' 输出：True
输入： 'I love python' 输出：False
输入： 'The upper pattern has not been test yet, so USA' 输出：True
def check_sentence(sentence):
# 特殊情况1:全大写单词正确
for word in sentence.upper().split():
if word.isupper():
continue
# 特殊情况2:四个特定单词正确性判断
for key in ['Python', 'Java', 'MachineLearning', 'DataMining']:
if key in sentence:
if key != sentence.split()[sentence.split().index(key)]:
return False
# 特殊情况3:数字+字母单词全大写
for word in sentence.split():
if word.isalnum() and word[0].isdigit():
if word != word.upper():
return False
# 一般情况:第一个单词首字母大写,其余小写
first_word = True
for word in sentence.split():
if first_word:
if word[0].islower():
return False
first_word = False
else:
if word[0].isupper():
return False
return True
sentence1 = 'I love Python'
sentence2 = 'python love me'
sentence3 = 'JUST DO IT'
sentence4 = 'I come from HK'
sentence5 = 'Machinelearning is so hot'
sentence6 = 'I love Python'
sentence7 = 'I love python'
sentence8 = 'The upper pattern has not been test yet, so USA'
print(check_sentence(sentence1))
print(check_sentence(sentence2))
print(check_sentence(sentence3))
print(check_sentence(sentence4))
print(check_sentence(sentence5))
print(check_sentence(sentence6))
print(check_sentence(sentence7))
print(check_sentence(sentence8))
代码：
def check_spelling(sentence):
words = sentence.split()
if len(words) == 0: # 句子为空，返回 False
return False
if words[0].islower(): # 第一个单词首字母为小写，返回 False
return False
for word in words:
if word.isupper() and len(word) > 1: # 全部为大写字母且不是单个字母，拼写正确
continue
elif word in ['Python', 'Java', 'MachineLearning', 'DataMining']: # 四个单词必须为双引号中给出的形式
continue
elif len(word) > 1 and word[0].isdigit() and word[1:].islower(): # 数字+字母混合形式，字母全部大写
if word[1:].isupper():
continue
else:
return False
elif not word.islower(): # 其他情况，单词不是全部小写，返回 False
return False
return True
测试：
print(check_spelling('I love Python')) # True
print(check_spelling('python love me')) # False
print(check_spelling('JUST DO IT')) # True
print(check_spelling('I come from HK')) #True
print(check_spelling('Machinelearning is so hot')) # False
print(check_spelling('I love Python')) # True
print(check_spelling('I love python')) # False
print(check_spelling('The upper pattern has not been test yet, so USA')) # True
下面是Python实现该任务的代码。代码思路是先对句子进行分词，然后按照题目要求判断每个单词的拼写是否正确。
import nltk
nltk.download("punkt")
def is_spelling_correct(sentence):
words = nltk.word_tokenize(sentence) # 对句子进行分词
for i, word in enumerate(words):
if word == "Python" or word == "Java" or word == "MachineLearning" or word == "DataMining": # 四个单词必须为双引号中给出的形式
if i == 0 or words[i-1][-1] != '"' or (i < len(words) - 1 and words[i+1][0] != '"'):
return False
elif word.isupper() and len(word) > 1: # 如果单词全部为大写，则拼写正确
continue
elif word.isupper() and len(word) == 1: # 如果单词只有一个字母，则拼写错误
return False
else:
if i == 0 and not word[0].isupper(): # 第一个单词首字母必须大写
return False
if i > 0 and words[i-1][-1] == '"': # 如果前一个单词以"结束，则当前单词拼写正确
continue
if word.isalpha() and not word.islower(): # 如果单词首字母不是大写且单词全部由字母构成，则拼写错误
return False
if word.isalnum() and word[0].isdigit() and word[1:].isupper(): # 数字和字母混合的形式，全部大写
continue
if word != "I" and not word.islower(): # 其他情况，单词必须小写
return False
return True
使用上述代码，可以像下面这样来测试：
print(is_spelling_correct("I love Python")) # True
print(is_spelling_correct("python love me")) # False
print(is_spelling_correct("JUST DO IT")) # True
print(is_spelling_correct("I come from HK")) # True
print(is_spelling_correct("Machinelearning is so hot")) # False
print(is_spelling_correct("I love Python")) # True
print(is_spelling_correct("I love python")) # False
print(is_spelling_correct("The upper pattern has not been test yet, so USA")) # True
输出结果如下所示：
True
False
True
True
False
True
False
True