Question

我想创建一个常量变量，其结构如下：

 const example_order_3_lines = [
  {
    order_id: 111_222_333,
    line_items:[
      {
        title: 'cookie',
        quantity: 5,
        space: 0.5,
      },
      {
        title: 'md meal',
        quantity: 3,
        space: 2.0,
      },
      {
        title: 'lg meal',
        quantity: 4,
        space: 3.0,
      },
      {
        title: 'soup',
        quantity: 2,
        space: 2.5,
      },
      {
        title: 'apple pie',
        quantity: 3,
        space: 1,
      }
    ],
  },
];

但是当我运行该单元格时出现此错误：

 File "<ipython-input-60-44a3630eacc1>", line 1
    const example_order_3_lines = [
                              ^
SyntaxError: invalid syntax

当我从变量中删除const时，会出现此错误：

   NameError                                 Traceback (most recent call last)
<ipython-input-64-a12c8a34587f> in <module>
      1 example_order_3_lines = [
      2  {
----> 3    order_id: 111_222_333,
      4    line_items:[
      5      {

NameError: name 'order_id' is not defined

有人可以帮我解决这个问题吗？

有我的主要功能：

function __main__() {
  const BAG_SIZE = 4;
  const results = solve(example_order_3_lines, BAG_SIZE);
  console.log('results: ', results[0].bags.length, JSON.stringify(results[0].bags, null, 2));
}
__main__();

主要任务是我想创建一个函数“ solve”，在其中使用“数量”和“空间”查找包装所需的最小袋子。我想为此使用背包方法。

Answer 1

您必须按照Shahroozevsky所述删除const。字典由key：value对组成。密钥必须是不变的。这意味着您可以将字符串，数字或元组用作字典键。

line_items：[ { “ title”：“ cookie”， “数量”：5 “空格”：0.5 }

https://www.tutorialspoint.com/python/python_dictionary.htm

Answer 2

有效的Python示例应如下所示：

example_order_3_lines = [
    {
        "order_id": "111_222_333",
        "line_items": [
            {
                "title": 'cookie',
                "quantity": 5,
                "space": 0.5,
            },
            {
                "title": 'md meal',
                "quantity": 3,
                "space": 2.0,
            },
            {
                "title": 'lg meal',
                "quantity": 4,
                "space": 3.0,
            },
            {
                "title": 'soup',
                "quantity": 2,
                "space": 2.5,
            },
            {
                "title": 'apple pie',
                "quantity": 3,
                "space": 1,
            }
        ],
    },
]

print(example_order_3_lines[0]['line_items'][0]['title'])

输出：cookie

SyntaxError：列表中的语法无效

2 个答案: