如何在字典中的列表中返回元組中的最大值？

Question

這是 RM Lerner 的 Python Workout 書中的一個練習。

我正在努力返回以下代碼的最大值：

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')

該函數應返回具有最高重復元素的單詞，在本例中為 e=3 的“elementary”，但它返回“example”。

我認為原因是它比較了單詞的第二個字母，並返回“x”作為最大值。 我不明白如何訪問元組值。 在返回部分使用outcome.values沒有幫助。

Answer 1

我們可以在outcome字典上使用for loop來檢查哪個單詞中哪個字母重復最多。

編碼

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")

輸出

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

Answer 2

由於outcome是元組列表的字典，因此您需要兩個max()來查找具有最高重復元素的單詞。 第一個max()查找單詞中重復次數最多的元素的計數，第二個max()查找計數最高的單詞。

保留您使用的數據結構， key參數需要如下所示： lambda word_maxchar: max(word_maxchar[1], key = lambda char_count: char_count[1])[1] 。 整個代碼如下所示：

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')

另請注意，為了遍歷字典的鍵和值，您需要使用outcome.items() 。

通過對你的數據結構稍作修改，我們可以實現代碼的稍微更好的可讀性：

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')