如果单词的第一个字母是元音，如何返回 1，否则返回 0。映射器（MapReduce）问题

这是我正在处理的 MapReduce 问题的第一部分。我需要一个函数，如果单词的第一个字母以元音开头，则返回 1，否则返回 0。

该程序通过将文本文件传输到映射器来在终端中运行，如下所示：

cat test.txt | python3 mapper.py

这是包含字符串的文本文件的预期输出its a beautiful life:

i 1 1 0   
t 1 0 0
s 1 0 0
a 1 1 1
b 1 0 0
e 1 0 0
a 1 0 0
u 1 0 0
t 1 0 0
i 1 0 0  
f 1 0 0
u 1 0 0
l 1 0 0
l 1 0 0
i 1 0 0 
f 1 0 0
e 1 0 1

我成功完成了前两列输出的分配，但第三列出现了问题。如果单词的第一个字母是元音，则应该生成 1，否则生成 0。

我当前的输出如下所示：

i 1 1 0
t 1 1 0
s 1 1 0
a 1 1 0
b 1 1 0
e 1 1 0
a 1 1 0
u 1 1 0
t 1 1 0
i 1 1 0
f 1 1 0
u 1 1 0
l 1 1 0
l 1 1 0
i 1 1 0
f 1 1 0
e 1 1 0

这是我到目前为止编写的代码：

import sys
import re
pattern = re.compile("^[a-z]+$") # matches purely alphabetic words
starting_vowels = re.compile("(^[aeiouAEIOU])") # matches starting vowels 
ending_vowels = re.compile("[aeiouAEIOU]$") # matches ending vowels
# starting_vowel_match = 0
ending_vowel_match = 0

def first_vowel():
    for token in tokens:
        if starting_vowels.match(token[0]):
            yield '1'
        else:
            yield '0'

for line in sys.stdin:
    line = line.strip() # removes leading and trailing whitespace
    tokens = line.split() # splits words into list, needed for part 2
    mashed_line = line.replace(" ","")
    lower_mashed_line = mashed_line.lower()
    for letter in lower_mashed_line: 
        if pattern.match(letter): # if pattern matches, prints 'word 1'
            print('%s 1' % letter, next(first_vowel()), ending_vowel_match)

分别迭代单词和字母，找出每个字母对应的单词，然后重置starting_vowel_match第一个字母之后：

import sys
import re

pattern = re.compile("^[a-z]+$")  # matches purely alphabetic words
starting_vowels = re.compile("(^[aeiouAEIOU])")  # matches starting vowels
ending_vowels = re.compile("[aeiouAEIOU]$")  # matches ending vowels
starting_vowel_match = 0
ending_vowel_match = 0

for line in sys.stdin:
    line = line.strip()  # removes leading and trailing whitespace
    words = line.lower().split()  # splits the line into words and converts to lowercase
    for word in words:
        starting_vowel_match = 1 if starting_vowels.match(word[0]) else 0
        # ternary operator, word[0] is the first letter of the word

        for letter in word:
            if pattern.match(letter):
                print("%s 1" % letter, starting_vowel_match, ending_vowel_match)
                starting_vowel_match = 0 # reset starting vowel match after first letter