如何在字典中的列表中返回元组中的最大值？

Question

这是 RM Lerner 的 Python Workout 书中的一个练习。

我正在努力返回以下代码的最大值：

def most_repeating_word(ls):
    listed = [x for x in ls.split()]
    outcome = {}
   
    for word in listed:
        max_char = []
        char_set = []
        for char in word:
            if char not in char_set:
                char_set.append(char)
                count = word.count(char)
                max_char.append((char,count))
        
        outcome[word] = (max_char)

    return max(outcome, key = lambda x: x[1])

most_repeating_word('this is an elementary test example')

该函数应返回具有最高重复元素的单词，在本例中为 e=3 的“elementary”，但它返回“example”。

我认为原因是它比较了单词的第二个字母，并返回“x”作为最大值。 我不明白如何访问元组值。 在返回部分使用outcome.values没有帮助。

Answer 1

我们可以在outcome字典上使用for loop来检查哪个单词中哪个字母重复最多。

编码

def most_repeating_word(ls):
    listed = [x for x in ls.split()]
    outcome = {}
   
    for word in listed:
        max_char = []
        char_set = []
        for char in word:
            if char not in char_set:
                char_set.append(char)
                count = word.count(char)
                max_char.append((char,count))
        
        outcome[word] = (max_char)
    
    repeating_word = ''
    repeating_letter = ''
    max_char_count = 0
    for key in outcome:
        for letter in outcome[key]:
            if letter[1] > max_char_count:
                repeating_word = key
                repeating_letter = letter[0]
                max_char_count = letter[1]

    return [repeating_word, repeating_letter, max_char_count]


data = most_repeating_word('this is an elementary test example')

print(f"The word {data[0]} ham most repeated letter {data[1]} which occurs {data[2]} times")

输出

The word elementary ham most repeated letter e which occurs 3 times

Answer 2

由于outcome是元组列表的字典，因此您需要两个max()来查找具有最高重复元素的单词。 第一个max()查找单词中重复次数最多的元素的计数，第二个max()查找计数最高的单词。

保留您使用的数据结构， key参数需要如下所示： lambda word_maxchar: max(word_maxchar[1], key = lambda char_count: char_count[1])[1] 。 整个代码如下所示：

def most_repeating_word(ls):
    listed = [x for x in ls.split()]
    outcome = {}
   
    for word in listed:
        max_char = []
        char_set = []
        for char in word:
            if char not in char_set:
                char_set.append(char)
                count = word.count(char)
                max_char.append((char,count))
        
        outcome[word] = (max_char)

    return max(outcome.items(), key = lambda word_maxchar: max(word_maxchar[1], key = lambda char_count: char_count[1])[1])[0]

most_repeating_word('this is an elementary test example')

另请注意，为了遍历字典的键和值，您需要使用outcome.items() 。

通过对你的数据结构稍作修改，我们可以实现代码的稍微更好的可读性：

def most_repeating_word(ls):
    listed = [x for x in ls.split()]
    outcome = {}
   
    for word in listed:
        max_char = []
        char_set = []
        for char in word:
            if char not in char_set:
                char_set.append(char)
                count = word.count(char)
                max_char.append((char,count))
            
        
        outcome[word] = max(max_char, key = lambda char_count: char_count[1])

    return max(outcome.items(), key = lambda x: x[1][1])[0]

most_repeating_word('this is an elementary test example')