Question

我有一个类似于以下的代码段，它将引发无效的语法错误：

static void Main(string[] args)
{
    var bob = new Dictionary<string, Dictionary<string, int>>();

    bob["10003"] = new Dictionary<string, int> {
        { "computer", 25 },
        { "desk", 23 },
        { "chair", 7 },
        { "score", 44} };
    bob["10004"] = new Dictionary<string, int> {
        { "computer", 35 },
        { "desk", 23 },
        { "chair", 7 },
        { "score", 77} };
    bob["10005"] = new Dictionary<string, int> {
        { "computer", 85 },
        { "desk", 23 },
        { "chair", 7 },
        { "score", 10} };

    var ordered = bob.OrderBy(z => z.Value["score"]).ToList();

    Console.WriteLine(ordered.First().Value["computer"]); // 85 since 10 is the lowest score
    Console.WriteLine(ordered.Last().Value["computer"]); // 35 since 77 is the highest score

    Console.ReadLine();
}

基本上，我希望lst = [0, 0, 0] new_lst = [lst[-1] = i + 1 for i in range(3)]是列表的列表，其中每个列表都是new_lst，但最后一个元素已更改。有任何想法如何在Python中执行此操作吗？

Answer 1

您只能在它们是独立语句时进行分配，即不在列表理解范围之内。在控制语句中，例如for或In [945]: lst = [0, 0, 0] In [946]: new_lst = [lst[:-1] + [i + 1] for i in range(3)] In [947]: new_lst Out[947]: [[0, 0, 1], [0, 0, 2], [0, 0, 3]] s

lst[:-1]

lst提取[i + 1]中的每个元素，但最后一个元素除外，^((?!550)\d{8}|(?!393)\d{5})$将附加到列表的末尾

如何在列表理解中修改Python列表的最后一个元素？

1 个答案: