打印嵌套列表中第二低分数得分者的姓名，并按 Python 中的字母顺序排列

Question

    if __name__ == '__main__':
    arr = []
        for _ in range(int(input())):
            name = input()
            arr.append(name)
            score = float(input())
            arr.append(score)

        array = [arr[i:i+2] for i in range(0, len(arr), 2)]
        marks = []
        for j in range(0, len(array)):
            marks.append(array[j][1])
        marks = list(map(float, marks))
        marks.sort()
        seclow = marks[1]
        for k in range(0, len(array)):
            if (seclow == float(array[k][1])):
                print(array[k][0])

**SAMPLE INPUT:**

    5
    Harry
    37.21
    Berry
    37.21
    Tina
    37.2
    Akriti
    41
    Harsh
    39

**EXPECTED OUTPUT:**

    BERRY
    HARRY

**MY OUTPUT:**

    HARRY
    BERRY

唯一的问题是按字母顺序对分数最低的名字进行排序。我应该使用列表来通过测试用例。那么，代码应该做哪些改动呢？

Answer 1

通过此处查看：https://ide.geeksforgeeks.org/fMD7OgxYC7

而不是定义列表。将其存储在字典中。这将为您提供 space 优化的解决方案。然后按值对字典进行排序。添加字典中有分数的名字。

尝试：

import collections
if __name__ == '__main__':
    arr = {}
    for _ in range(int(input())):
        name = input()
        score = float(input())
        arr[name] = score

    dd = collections.defaultdict(list)

    for k,v in arr.items():
        dd[v].append(k)

    x = sorted(dd.items())
    sec_low = sorted(x[1][1])
    for i in sec_low:
        print(i)

输入：

5
Harry
37.21
Berry
37.21
Tina
37.2
Akriti
41
Harsh
39

输出：

Berry
Harry

x:

[(37.2, ['Tina']),
 (37.21, ['Harry', 'Berry']),
 (39.0, ['Harsh']),
 (41.0, ['Akriti'])]

Answer 2

不使用任何导入且代码更少，可以通过这种方式完成。我还把它放到了一个函数中，只是为了让它更干净一点，这样你就可以在需要的时候在其他地方重用它。

def main():
    scores_dict = {}
    for _ in range(int(input())):
        name, score = input(), float(input())

        if score not in scores_dict:
            scores_dict[score] = []
        scores_dict[score].append(name)

    # Delete the min score key and names so that we can grab the second min
    del scores_dict[min(scores_dict.keys())]

    # Get new min score.
    min_score = min(scores_dict.keys())

    # Sort new min score.
    scores_dict[min_score].sort()
    # Print each name in results
    [print(i) for i in scores_dict[min_score]]

if __name__ == '__main__':
    main()

Answer 3

处理重复的最低值和重复的次低值。

示例输入：{“hri”：6.2，“dav”：1.1，“asv”：1.1，“wrs”：12.3，“dup”：6.2，“awe”：43.2，“asw”：22.2 "asd":6.2}

输出：['asd', 'dup', 'hri'] 可以打印连接到 "\n"

def lowest_scores(names_scores):
    
        lowest_score=min(names_scores.values())
        
        lowscorers=[]
    
        low_scorer_dict = { k : v for k,v in names_scores.items() if v != lowest_score}
        
        second_lowest_score = min(low_scorer_dict.values())
    
        for k,v in low_scorer_dict.items():
            if v == second_lowest_score:
                lowscorers.append(k)
            
        return sorted(lowscorers)

打印嵌套列表中第二低分数得分者的姓名，并按 Python 中的字母顺序排列

Printing name of second lowest mark scorer in a nested list and arranging in alphabetical order in Python

python

list

nested-lists

python-3.x