2023-02-26 20:16:55 +08:00
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# 列表(List)
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2022-11-22 17:47:26 +08:00
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2023-01-07 20:34:32 +08:00
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**由于长度不可变,数组的实用性大大降低**。在很多情况下,我们事先并不知道会输入多少数据,这就为数组长度的选择带来了很大困难。长度选小了,需要在添加数据中频繁地扩容数组;长度选大了,又造成内存空间的浪费。
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2022-11-22 17:47:26 +08:00
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为了解决此问题,诞生了一种被称为「列表 List」的数据结构。列表可以被理解为长度可变的数组,因此也常被称为「动态数组 Dynamic Array」。列表基于数组实现,继承了数组的优点,同时还可以在程序运行中实时扩容。在列表中,我们可以自由地添加元素,而不用担心超过容量限制。
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2023-02-16 03:39:01 +08:00
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## 列表常用操作
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2022-11-22 17:47:26 +08:00
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2023-01-07 20:34:32 +08:00
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**初始化列表**。我们通常会使用到“无初始值”和“有初始值”的两种初始化方法。
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2022-11-22 17:47:26 +08:00
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=== "Java"
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```java title="list.java"
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/* 初始化列表 */
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2022-12-21 01:37:58 +08:00
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// 无初始值
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List<Integer> list1 = new ArrayList<>();
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// 有初始值(注意数组的元素类型需为 int[] 的包装类 Integer[])
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2022-11-22 17:47:26 +08:00
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Integer[] numbers = new Integer[] { 1, 3, 2, 5, 4 };
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List<Integer> list = new ArrayList<>(Arrays.asList(numbers));
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```
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=== "C++"
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```cpp title="list.cpp"
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2022-11-27 19:07:35 +08:00
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/* 初始化列表 */
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2022-12-21 01:37:58 +08:00
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// 需注意,C++ 中 vector 即是本文描述的 list
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// 无初始值
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vector<int> list1;
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// 有初始值
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2022-11-27 19:07:35 +08:00
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vector<int> list = { 1, 3, 2, 5, 4 };
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2022-11-22 17:47:26 +08:00
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```
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=== "Python"
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```python title="list.py"
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2022-11-25 03:59:38 +08:00
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""" 初始化列表 """
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2022-12-21 01:37:58 +08:00
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# 无初始值
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list1 = []
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# 有初始值
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2022-11-25 03:59:38 +08:00
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list = [1, 3, 2, 5, 4]
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2022-11-22 17:47:26 +08:00
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```
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2022-12-03 01:31:29 +08:00
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=== "Go"
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2022-12-18 14:55:14 +08:00
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```go title="list_test.go"
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/* 初始化列表 */
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2022-12-21 01:37:58 +08:00
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// 无初始值
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list1 := []int
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// 有初始值
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2022-12-18 14:55:14 +08:00
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list := []int{1, 3, 2, 5, 4}
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2022-12-03 01:31:29 +08:00
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```
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=== "JavaScript"
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2023-02-08 04:27:55 +08:00
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```javascript title="list.js"
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2022-12-12 21:30:55 +08:00
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/* 初始化列表 */
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2022-12-21 01:37:58 +08:00
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// 无初始值
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const list1 = [];
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// 有初始值
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2022-12-12 21:30:55 +08:00
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const list = [1, 3, 2, 5, 4];
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2022-12-03 01:31:29 +08:00
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```
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=== "TypeScript"
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```typescript title="list.ts"
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2022-12-12 03:22:40 +08:00
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/* 初始化列表 */
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2022-12-21 01:37:58 +08:00
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// 无初始值
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const list1: number[] = [];
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// 有初始值
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2022-12-12 03:22:40 +08:00
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const list: number[] = [1, 3, 2, 5, 4];
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2022-12-03 01:31:29 +08:00
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```
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=== "C"
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```c title="list.c"
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```
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=== "C#"
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```csharp title="list.cs"
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2022-12-23 15:42:02 +08:00
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/* 初始化列表 */
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// 无初始值
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List<int> list1 = new ();
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2023-02-09 19:45:35 +08:00
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// 有初始值
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2022-12-23 15:42:02 +08:00
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int[] numbers = new int[] { 1, 3, 2, 5, 4 };
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List<int> list = numbers.ToList();
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2022-12-03 01:31:29 +08:00
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```
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2023-01-08 19:41:05 +08:00
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=== "Swift"
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```swift title="list.swift"
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2023-01-08 23:44:13 +08:00
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/* 初始化列表 */
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// 无初始值
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let list1: [Int] = []
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// 有初始值
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var list = [1, 3, 2, 5, 4]
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2023-01-08 19:41:05 +08:00
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```
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2023-02-01 22:03:04 +08:00
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=== "Zig"
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```zig title="list.zig"
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2023-02-03 19:15:34 +08:00
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// 初始化列表
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var list = std.ArrayList(i32).init(std.heap.page_allocator);
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defer list.deinit();
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try list.appendSlice(&[_]i32{ 1, 3, 2, 5, 4 });
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2023-02-01 22:03:04 +08:00
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```
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2023-01-07 20:34:32 +08:00
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**访问与更新元素**。列表的底层数据结构是数组,因此可以在 $O(1)$ 时间内访问与更新元素,效率很高。
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2022-11-22 17:47:26 +08:00
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=== "Java"
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```java title="list.java"
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/* 访问元素 */
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int num = list.get(1); // 访问索引 1 处的元素
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/* 更新元素 */
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list.set(1, 0); // 将索引 1 处的元素更新为 0
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```
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=== "C++"
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```cpp title="list.cpp"
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2022-11-27 19:07:35 +08:00
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/* 访问元素 */
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int num = list[1]; // 访问索引 1 处的元素
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2022-11-22 17:47:26 +08:00
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2022-11-27 19:07:35 +08:00
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/* 更新元素 */
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list[1] = 0; // 将索引 1 处的元素更新为 0
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2022-11-22 17:47:26 +08:00
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```
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=== "Python"
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```python title="list.py"
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2022-11-25 03:59:38 +08:00
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""" 访问元素 """
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num = list[1] # 访问索引 1 处的元素
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""" 更新元素 """
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list[1] = 0 # 将索引 1 处的元素更新为 0
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2022-11-22 17:47:26 +08:00
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```
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2022-12-03 01:31:29 +08:00
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=== "Go"
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2022-12-18 14:55:14 +08:00
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```go title="list_test.go"
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/* 访问元素 */
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num := list[1] // 访问索引 1 处的元素
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2022-12-03 01:31:29 +08:00
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2022-12-18 14:55:14 +08:00
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/* 更新元素 */
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list[1] = 0 // 将索引 1 处的元素更新为 0
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2022-12-03 01:31:29 +08:00
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```
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=== "JavaScript"
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2023-02-08 04:27:55 +08:00
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```javascript title="list.js"
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2022-12-12 21:30:55 +08:00
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/* 访问元素 */
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2022-12-24 17:05:58 +08:00
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const num = list[1]; // 访问索引 1 处的元素
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2022-12-03 01:31:29 +08:00
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2022-12-12 21:30:55 +08:00
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/* 更新元素 */
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2022-12-24 17:05:58 +08:00
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list[1] = 0; // 将索引 1 处的元素更新为 0
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2022-12-03 01:31:29 +08:00
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```
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=== "TypeScript"
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```typescript title="list.ts"
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2022-12-12 03:22:40 +08:00
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/* 访问元素 */
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2022-12-24 17:05:58 +08:00
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const num: number = list[1]; // 访问索引 1 处的元素
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2022-12-03 01:31:29 +08:00
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2022-12-12 03:22:40 +08:00
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/* 更新元素 */
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2022-12-24 17:05:58 +08:00
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list[1] = 0; // 将索引 1 处的元素更新为 0
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2022-12-03 01:31:29 +08:00
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```
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=== "C"
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```c title="list.c"
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```
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=== "C#"
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```csharp title="list.cs"
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2022-12-23 15:42:02 +08:00
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/* 访问元素 */
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2022-12-24 17:05:58 +08:00
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int num = list[1]; // 访问索引 1 处的元素
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2022-12-03 01:31:29 +08:00
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2022-12-23 15:42:02 +08:00
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/* 更新元素 */
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2022-12-24 17:05:58 +08:00
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list[1] = 0; // 将索引 1 处的元素更新为 0
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2022-12-03 01:31:29 +08:00
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```
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2023-01-08 19:41:05 +08:00
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=== "Swift"
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```swift title="list.swift"
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2023-01-08 23:44:13 +08:00
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/* 访问元素 */
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let num = list[1] // 访问索引 1 处的元素
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2023-01-08 19:41:05 +08:00
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2023-01-08 23:44:13 +08:00
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/* 更新元素 */
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list[1] = 0 // 将索引 1 处的元素更新为 0
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2023-01-08 19:41:05 +08:00
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```
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2023-02-01 22:03:04 +08:00
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=== "Zig"
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```zig title="list.zig"
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2023-02-03 19:15:34 +08:00
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// 访问元素
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var num = list.items[1]; // 访问索引 1 处的元素
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2023-02-01 22:03:04 +08:00
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2023-02-03 19:15:34 +08:00
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// 更新元素
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list.items[1] = 0; // 将索引 1 处的元素更新为 0
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2023-02-01 22:03:04 +08:00
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```
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2023-01-07 20:34:32 +08:00
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**在列表中添加、插入、删除元素**。相对于数组,列表可以自由地添加与删除元素。在列表尾部添加元素的时间复杂度为 $O(1)$ ,但是插入与删除元素的效率仍与数组一样低,时间复杂度为 $O(N)$ 。
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2022-11-22 17:47:26 +08:00
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=== "Java"
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```java title="list.java"
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/* 清空列表 */
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list.clear();
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/* 尾部添加元素 */
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list.add(1);
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list.add(3);
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list.add(2);
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list.add(5);
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list.add(4);
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/* 中间插入元素 */
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list.add(3, 6); // 在索引 3 处插入数字 6
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/* 删除元素 */
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list.remove(3); // 删除索引 3 处的元素
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```
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=== "C++"
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```cpp title="list.cpp"
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2022-11-27 19:07:35 +08:00
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/* 清空列表 */
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list.clear();
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/* 尾部添加元素 */
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list.push_back(1);
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list.push_back(3);
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list.push_back(2);
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list.push_back(5);
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list.push_back(4);
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/* 中间插入元素 */
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list.insert(list.begin() + 3, 6); // 在索引 3 处插入数字 6
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2022-11-22 17:47:26 +08:00
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2022-11-27 19:07:35 +08:00
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/* 删除元素 */
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list.erase(list.begin() + 3); // 删除索引 3 处的元素
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2022-11-22 17:47:26 +08:00
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```
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=== "Python"
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```python title="list.py"
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2022-11-25 03:59:38 +08:00
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""" 清空列表 """
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list.clear()
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""" 尾部添加元素 """
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list.append(1)
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list.append(3)
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list.append(2)
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list.append(5)
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list.append(4)
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""" 中间插入元素 """
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list.insert(3, 6) # 在索引 3 处插入数字 6
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""" 删除元素 """
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list.pop(3) # 删除索引 3 处的元素
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2022-11-22 17:47:26 +08:00
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```
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2022-12-03 01:31:29 +08:00
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=== "Go"
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|
|
|
|
|
2022-12-18 14:55:14 +08:00
|
|
|
|
```go title="list_test.go"
|
|
|
|
|
/* 清空列表 */
|
2022-12-18 21:57:29 +08:00
|
|
|
|
list = nil
|
2022-12-18 14:55:14 +08:00
|
|
|
|
|
|
|
|
|
/* 尾部添加元素 */
|
|
|
|
|
list = append(list, 1)
|
|
|
|
|
list = append(list, 3)
|
|
|
|
|
list = append(list, 2)
|
|
|
|
|
list = append(list, 5)
|
|
|
|
|
list = append(list, 4)
|
2022-12-03 01:31:29 +08:00
|
|
|
|
|
2022-12-18 14:55:14 +08:00
|
|
|
|
/* 中间插入元素 */
|
|
|
|
|
list = append(list[:3], append([]int{6}, list[3:]...)...) // 在索引 3 处插入数字 6
|
|
|
|
|
|
|
|
|
|
/* 删除元素 */
|
|
|
|
|
list = append(list[:3], list[4:]...) // 删除索引 3 处的元素
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "JavaScript"
|
|
|
|
|
|
2023-02-08 04:27:55 +08:00
|
|
|
|
```javascript title="list.js"
|
2022-12-12 21:30:55 +08:00
|
|
|
|
/* 清空列表 */
|
|
|
|
|
list.length = 0;
|
|
|
|
|
|
|
|
|
|
/* 尾部添加元素 */
|
|
|
|
|
list.push(1);
|
|
|
|
|
list.push(3);
|
|
|
|
|
list.push(2);
|
|
|
|
|
list.push(5);
|
|
|
|
|
list.push(4);
|
|
|
|
|
|
|
|
|
|
/* 中间插入元素 */
|
|
|
|
|
list.splice(3, 0, 6);
|
2022-12-03 01:31:29 +08:00
|
|
|
|
|
2022-12-12 21:30:55 +08:00
|
|
|
|
/* 删除元素 */
|
|
|
|
|
list.splice(3, 1);
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "TypeScript"
|
|
|
|
|
|
|
|
|
|
```typescript title="list.ts"
|
2022-12-12 03:22:40 +08:00
|
|
|
|
/* 清空列表 */
|
|
|
|
|
list.length = 0;
|
|
|
|
|
|
|
|
|
|
/* 尾部添加元素 */
|
|
|
|
|
list.push(1);
|
|
|
|
|
list.push(3);
|
|
|
|
|
list.push(2);
|
|
|
|
|
list.push(5);
|
|
|
|
|
list.push(4);
|
|
|
|
|
|
|
|
|
|
/* 中间插入元素 */
|
|
|
|
|
list.splice(3, 0, 6);
|
2022-12-03 01:31:29 +08:00
|
|
|
|
|
2022-12-12 03:22:40 +08:00
|
|
|
|
/* 删除元素 */
|
|
|
|
|
list.splice(3, 1);
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C"
|
|
|
|
|
|
|
|
|
|
```c title="list.c"
|
|
|
|
|
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C#"
|
|
|
|
|
|
|
|
|
|
```csharp title="list.cs"
|
2022-12-23 15:42:02 +08:00
|
|
|
|
/* 清空列表 */
|
|
|
|
|
list.Clear();
|
|
|
|
|
|
|
|
|
|
/* 尾部添加元素 */
|
|
|
|
|
list.Add(1);
|
|
|
|
|
list.Add(3);
|
|
|
|
|
list.Add(2);
|
|
|
|
|
list.Add(5);
|
|
|
|
|
list.Add(4);
|
2022-12-03 01:31:29 +08:00
|
|
|
|
|
2022-12-23 15:42:02 +08:00
|
|
|
|
/* 中间插入元素 */
|
|
|
|
|
list.Insert(3, 6);
|
|
|
|
|
|
|
|
|
|
/* 删除元素 */
|
2022-12-24 16:15:41 +08:00
|
|
|
|
list.RemoveAt(3);
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-01-08 19:41:05 +08:00
|
|
|
|
=== "Swift"
|
|
|
|
|
|
|
|
|
|
```swift title="list.swift"
|
2023-01-08 23:44:13 +08:00
|
|
|
|
/* 清空列表 */
|
|
|
|
|
list.removeAll()
|
|
|
|
|
|
|
|
|
|
/* 尾部添加元素 */
|
|
|
|
|
list.append(1)
|
|
|
|
|
list.append(3)
|
|
|
|
|
list.append(2)
|
|
|
|
|
list.append(5)
|
|
|
|
|
list.append(4)
|
|
|
|
|
|
|
|
|
|
/* 中间插入元素 */
|
|
|
|
|
list.insert(6, at: 3) // 在索引 3 处插入数字 6
|
2023-01-08 19:41:05 +08:00
|
|
|
|
|
2023-01-08 23:44:13 +08:00
|
|
|
|
/* 删除元素 */
|
|
|
|
|
list.remove(at: 3) // 删除索引 3 处的元素
|
2023-01-08 19:41:05 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-02-01 22:03:04 +08:00
|
|
|
|
=== "Zig"
|
|
|
|
|
|
|
|
|
|
```zig title="list.zig"
|
2023-02-03 19:15:34 +08:00
|
|
|
|
// 清空列表
|
|
|
|
|
list.clearRetainingCapacity();
|
|
|
|
|
|
|
|
|
|
// 尾部添加元素
|
|
|
|
|
try list.append(1);
|
|
|
|
|
try list.append(3);
|
|
|
|
|
try list.append(2);
|
|
|
|
|
try list.append(5);
|
|
|
|
|
try list.append(4);
|
|
|
|
|
|
|
|
|
|
// 中间插入元素
|
|
|
|
|
try list.insert(3, 6); // 在索引 3 处插入数字 6
|
2023-02-01 22:03:04 +08:00
|
|
|
|
|
2023-02-03 19:15:34 +08:00
|
|
|
|
// 删除元素
|
|
|
|
|
_ = list.orderedRemove(3); // 删除索引 3 处的元素
|
2023-02-01 22:03:04 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-01-07 20:34:32 +08:00
|
|
|
|
**遍历列表**。与数组一样,列表可以使用索引遍历,也可以使用 `for-each` 直接遍历。
|
2022-11-22 17:47:26 +08:00
|
|
|
|
|
|
|
|
|
=== "Java"
|
|
|
|
|
|
|
|
|
|
```java title="list.java"
|
|
|
|
|
/* 通过索引遍历列表 */
|
|
|
|
|
int count = 0;
|
|
|
|
|
for (int i = 0; i < list.size(); i++) {
|
|
|
|
|
count++;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/* 直接遍历列表元素 */
|
|
|
|
|
count = 0;
|
|
|
|
|
for (int n : list) {
|
|
|
|
|
count++;
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C++"
|
|
|
|
|
|
|
|
|
|
```cpp title="list.cpp"
|
2022-11-27 19:07:35 +08:00
|
|
|
|
/* 通过索引遍历列表 */
|
|
|
|
|
int count = 0;
|
|
|
|
|
for (int i = 0; i < list.size(); i++) {
|
|
|
|
|
count++;
|
|
|
|
|
}
|
2022-11-22 17:47:26 +08:00
|
|
|
|
|
2022-11-27 19:07:35 +08:00
|
|
|
|
/* 直接遍历列表元素 */
|
|
|
|
|
count = 0;
|
|
|
|
|
for (int n : list) {
|
|
|
|
|
count++;
|
|
|
|
|
}
|
2022-11-22 17:47:26 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "Python"
|
|
|
|
|
|
|
|
|
|
```python title="list.py"
|
2022-11-25 03:59:38 +08:00
|
|
|
|
""" 通过索引遍历列表 """
|
|
|
|
|
count = 0
|
|
|
|
|
for i in range(len(list)):
|
|
|
|
|
count += 1
|
|
|
|
|
|
|
|
|
|
""" 直接遍历列表元素 """
|
|
|
|
|
count = 0
|
|
|
|
|
for n in list:
|
|
|
|
|
count += 1
|
2022-11-22 17:47:26 +08:00
|
|
|
|
```
|
|
|
|
|
|
2022-12-03 01:31:29 +08:00
|
|
|
|
=== "Go"
|
|
|
|
|
|
2022-12-18 14:55:14 +08:00
|
|
|
|
```go title="list_test.go"
|
|
|
|
|
/* 通过索引遍历列表 */
|
|
|
|
|
count := 0
|
|
|
|
|
for i := 0; i < len(list); i++ {
|
|
|
|
|
count++
|
|
|
|
|
}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
|
2022-12-18 14:55:14 +08:00
|
|
|
|
/* 直接遍历列表元素 */
|
|
|
|
|
count = 0
|
2022-12-24 16:15:41 +08:00
|
|
|
|
for range list {
|
|
|
|
|
count++
|
|
|
|
|
}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "JavaScript"
|
|
|
|
|
|
2023-02-08 04:27:55 +08:00
|
|
|
|
```javascript title="list.js"
|
2022-12-12 21:30:55 +08:00
|
|
|
|
/* 通过索引遍历列表 */
|
|
|
|
|
let count = 0;
|
|
|
|
|
for (let i = 0; i < list.length; i++) {
|
|
|
|
|
count++;
|
|
|
|
|
}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
|
2022-12-12 21:30:55 +08:00
|
|
|
|
/* 直接遍历列表元素 */
|
|
|
|
|
count = 0;
|
|
|
|
|
for (const n of list) {
|
|
|
|
|
count++;
|
|
|
|
|
}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "TypeScript"
|
|
|
|
|
|
|
|
|
|
```typescript title="list.ts"
|
2022-12-12 03:22:40 +08:00
|
|
|
|
/* 通过索引遍历列表 */
|
|
|
|
|
let count = 0;
|
|
|
|
|
for (let i = 0; i < list.length; i++) {
|
|
|
|
|
count++;
|
|
|
|
|
}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
|
2022-12-12 03:22:40 +08:00
|
|
|
|
/* 直接遍历列表元素 */
|
|
|
|
|
count = 0;
|
|
|
|
|
for (const n of list) {
|
|
|
|
|
count++;
|
|
|
|
|
}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C"
|
|
|
|
|
|
|
|
|
|
```c title="list.c"
|
|
|
|
|
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C#"
|
|
|
|
|
|
|
|
|
|
```csharp title="list.cs"
|
2022-12-23 15:42:02 +08:00
|
|
|
|
/* 通过索引遍历列表 */
|
|
|
|
|
int count = 0;
|
|
|
|
|
for (int i = 0; i < list.Count(); i++)
|
|
|
|
|
{
|
|
|
|
|
count++;
|
|
|
|
|
}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
|
2022-12-23 15:42:02 +08:00
|
|
|
|
/* 直接遍历列表元素 */
|
|
|
|
|
count = 0;
|
|
|
|
|
foreach (int n in list)
|
|
|
|
|
{
|
|
|
|
|
count++;
|
|
|
|
|
}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-01-08 19:41:05 +08:00
|
|
|
|
=== "Swift"
|
|
|
|
|
|
|
|
|
|
```swift title="list.swift"
|
2023-01-08 23:44:13 +08:00
|
|
|
|
/* 通过索引遍历列表 */
|
|
|
|
|
var count = 0
|
|
|
|
|
for _ in list.indices {
|
|
|
|
|
count += 1
|
|
|
|
|
}
|
2023-01-08 19:41:05 +08:00
|
|
|
|
|
2023-01-08 23:44:13 +08:00
|
|
|
|
/* 直接遍历列表元素 */
|
|
|
|
|
count = 0
|
|
|
|
|
for _ in list {
|
|
|
|
|
count += 1
|
|
|
|
|
}
|
2023-01-08 19:41:05 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-02-01 22:03:04 +08:00
|
|
|
|
=== "Zig"
|
|
|
|
|
|
|
|
|
|
```zig title="list.zig"
|
2023-02-03 19:15:34 +08:00
|
|
|
|
// 通过索引遍历列表
|
|
|
|
|
var count: i32 = 0;
|
|
|
|
|
var i: i32 = 0;
|
|
|
|
|
while (i < list.items.len) : (i += 1) {
|
|
|
|
|
count += 1;
|
|
|
|
|
}
|
2023-02-01 22:03:04 +08:00
|
|
|
|
|
2023-02-03 19:15:34 +08:00
|
|
|
|
// 直接遍历列表元素
|
|
|
|
|
count = 0;
|
|
|
|
|
for (list.items) |_| {
|
|
|
|
|
count += 1;
|
|
|
|
|
}
|
2023-02-01 22:03:04 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-01-07 20:34:32 +08:00
|
|
|
|
**拼接两个列表**。再创建一个新列表 `list1` ,我们可以将其中一个列表拼接到另一个的尾部。
|
2022-11-22 17:47:26 +08:00
|
|
|
|
|
|
|
|
|
=== "Java"
|
|
|
|
|
|
|
|
|
|
```java title="list.java"
|
|
|
|
|
/* 拼接两个列表 */
|
|
|
|
|
List<Integer> list1 = new ArrayList<>(Arrays.asList(new Integer[] { 6, 8, 7, 10, 9 }));
|
|
|
|
|
list.addAll(list1); // 将列表 list1 拼接到 list 之后
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C++"
|
|
|
|
|
|
|
|
|
|
```cpp title="list.cpp"
|
2022-11-27 19:07:35 +08:00
|
|
|
|
/* 拼接两个列表 */
|
|
|
|
|
vector<int> list1 = { 6, 8, 7, 10, 9 };
|
|
|
|
|
// 将列表 list1 拼接到 list 之后
|
|
|
|
|
list.insert(list.end(), list1.begin(), list1.end());
|
2022-11-22 17:47:26 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "Python"
|
|
|
|
|
|
|
|
|
|
```python title="list.py"
|
2022-11-25 03:59:38 +08:00
|
|
|
|
""" 拼接两个列表 """
|
|
|
|
|
list1 = [6, 8, 7, 10, 9]
|
|
|
|
|
list += list1 # 将列表 list1 拼接到 list 之后
|
2022-11-22 17:47:26 +08:00
|
|
|
|
```
|
|
|
|
|
|
2022-12-03 01:31:29 +08:00
|
|
|
|
=== "Go"
|
|
|
|
|
|
2022-12-18 14:55:14 +08:00
|
|
|
|
```go title="list_test.go"
|
|
|
|
|
/* 拼接两个列表 */
|
|
|
|
|
list1 := []int{6, 8, 7, 10, 9}
|
|
|
|
|
list = append(list, list1...) // 将列表 list1 拼接到 list 之后
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "JavaScript"
|
|
|
|
|
|
2023-02-08 04:27:55 +08:00
|
|
|
|
```javascript title="list.js"
|
2022-12-12 21:30:55 +08:00
|
|
|
|
/* 拼接两个列表 */
|
|
|
|
|
const list1 = [6, 8, 7, 10, 9];
|
2022-12-24 17:05:58 +08:00
|
|
|
|
list.push(...list1); // 将列表 list1 拼接到 list 之后
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "TypeScript"
|
|
|
|
|
|
|
|
|
|
```typescript title="list.ts"
|
2022-12-12 03:22:40 +08:00
|
|
|
|
/* 拼接两个列表 */
|
|
|
|
|
const list1: number[] = [6, 8, 7, 10, 9];
|
2022-12-24 17:05:58 +08:00
|
|
|
|
list.push(...list1); // 将列表 list1 拼接到 list 之后
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C"
|
|
|
|
|
|
|
|
|
|
```c title="list.c"
|
|
|
|
|
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C#"
|
|
|
|
|
|
|
|
|
|
```csharp title="list.cs"
|
2022-12-23 15:42:02 +08:00
|
|
|
|
/* 拼接两个列表 */
|
|
|
|
|
List<int> list1 = new() { 6, 8, 7, 10, 9 };
|
2022-12-24 17:05:58 +08:00
|
|
|
|
list.AddRange(list1); // 将列表 list1 拼接到 list 之后
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-01-08 19:41:05 +08:00
|
|
|
|
=== "Swift"
|
|
|
|
|
|
|
|
|
|
```swift title="list.swift"
|
2023-01-08 23:44:13 +08:00
|
|
|
|
/* 拼接两个列表 */
|
|
|
|
|
let list1 = [6, 8, 7, 10, 9]
|
|
|
|
|
list.append(contentsOf: list1) // 将列表 list1 拼接到 list 之后
|
2023-01-08 19:41:05 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-02-01 22:03:04 +08:00
|
|
|
|
=== "Zig"
|
|
|
|
|
|
|
|
|
|
```zig title="list.zig"
|
2023-02-03 19:15:34 +08:00
|
|
|
|
// 拼接两个列表
|
|
|
|
|
var list1 = std.ArrayList(i32).init(std.heap.page_allocator);
|
|
|
|
|
defer list1.deinit();
|
|
|
|
|
try list1.appendSlice(&[_]i32{ 6, 8, 7, 10, 9 });
|
|
|
|
|
try list.insertSlice(list.items.len, list1.items); // 将列表 list1 拼接到 list 之后
|
2023-02-01 22:03:04 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-01-07 20:34:32 +08:00
|
|
|
|
**排序列表**。排序也是常用的方法之一,完成列表排序后,我们就可以使用在数组类算法题中经常考察的「二分查找」和「双指针」算法了。
|
2022-11-22 17:47:26 +08:00
|
|
|
|
|
|
|
|
|
=== "Java"
|
|
|
|
|
|
|
|
|
|
```java title="list.java"
|
|
|
|
|
/* 排序列表 */
|
|
|
|
|
Collections.sort(list); // 排序后,列表元素从小到大排列
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C++"
|
|
|
|
|
|
|
|
|
|
```cpp title="list.cpp"
|
2022-11-27 19:07:35 +08:00
|
|
|
|
/* 排序列表 */
|
|
|
|
|
sort(list.begin(), list.end()); // 排序后,列表元素从小到大排列
|
2022-11-22 17:47:26 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "Python"
|
|
|
|
|
|
|
|
|
|
```python title="list.py"
|
2022-11-25 03:59:38 +08:00
|
|
|
|
""" 排序列表 """
|
|
|
|
|
list.sort() # 排序后,列表元素从小到大排列
|
2022-11-22 17:47:26 +08:00
|
|
|
|
```
|
|
|
|
|
|
2022-12-03 01:31:29 +08:00
|
|
|
|
=== "Go"
|
|
|
|
|
|
2022-12-18 14:55:14 +08:00
|
|
|
|
```go title="list_test.go"
|
|
|
|
|
/* 排序列表 */
|
|
|
|
|
sort.Ints(list) // 排序后,列表元素从小到大排列
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "JavaScript"
|
|
|
|
|
|
2023-02-08 04:27:55 +08:00
|
|
|
|
```javascript title="list.js"
|
2022-12-12 21:30:55 +08:00
|
|
|
|
/* 排序列表 */
|
2022-12-24 17:05:58 +08:00
|
|
|
|
list.sort((a, b) => a - b); // 排序后,列表元素从小到大排列
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "TypeScript"
|
|
|
|
|
|
|
|
|
|
```typescript title="list.ts"
|
2022-12-12 03:22:40 +08:00
|
|
|
|
/* 排序列表 */
|
|
|
|
|
list.sort((a, b) => a - b); // 排序后,列表元素从小到大排列
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C"
|
|
|
|
|
|
|
|
|
|
```c title="list.c"
|
|
|
|
|
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C#"
|
|
|
|
|
|
|
|
|
|
```csharp title="list.cs"
|
2022-12-23 15:42:02 +08:00
|
|
|
|
/* 排序列表 */
|
|
|
|
|
list.Sort(); // 排序后,列表元素从小到大排列
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-01-08 19:41:05 +08:00
|
|
|
|
=== "Swift"
|
|
|
|
|
|
|
|
|
|
```swift title="list.swift"
|
2023-01-08 23:44:13 +08:00
|
|
|
|
/* 排序列表 */
|
|
|
|
|
list.sort() // 排序后,列表元素从小到大排列
|
2023-01-08 19:41:05 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-02-01 22:03:04 +08:00
|
|
|
|
=== "Zig"
|
|
|
|
|
|
|
|
|
|
```zig title="list.zig"
|
2023-02-03 19:15:34 +08:00
|
|
|
|
// 排序列表
|
|
|
|
|
std.sort.sort(i32, list.items, {}, comptime std.sort.asc(i32));
|
2023-02-01 22:03:04 +08:00
|
|
|
|
```
|
|
|
|
|
|
2023-02-16 03:39:01 +08:00
|
|
|
|
## 列表简易实现 *
|
2022-11-22 17:47:26 +08:00
|
|
|
|
|
|
|
|
|
为了帮助加深对列表的理解,我们在此提供一个列表的简易版本的实现。需要关注三个核心点:
|
|
|
|
|
|
2023-01-09 22:39:30 +08:00
|
|
|
|
- **初始容量**:选取一个合理的数组的初始容量 `initialCapacity` 。在本示例中,我们选择 10 作为初始容量。
|
|
|
|
|
- **数量记录**:需要声明一个变量 `size` ,用来记录列表当前有多少个元素,并随着元素插入与删除实时更新。根据此变量,可以定位列表的尾部,以及判断是否需要扩容。
|
|
|
|
|
- **扩容机制**:插入元素有可能导致超出列表容量,此时需要扩容列表,方法是建立一个更大的数组来替换当前数组。需要给定一个扩容倍数 `extendRatio` ,在本示例中,我们规定每次将数组扩容至之前的 2 倍。
|
2022-11-22 17:47:26 +08:00
|
|
|
|
|
|
|
|
|
本示例是为了帮助读者对如何实现列表产生直观的认识。实际编程语言中,列表的实现远比以下代码复杂且标准,感兴趣的读者可以查阅源码学习。
|
|
|
|
|
|
|
|
|
|
=== "Java"
|
|
|
|
|
|
|
|
|
|
```java title="my_list.java"
|
2023-02-07 04:43:52 +08:00
|
|
|
|
[class]{MyList}-[func]{}
|
2022-11-22 17:47:26 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C++"
|
|
|
|
|
|
|
|
|
|
```cpp title="my_list.cpp"
|
2023-02-08 04:17:26 +08:00
|
|
|
|
[class]{MyList}-[func]{}
|
2022-11-22 17:47:26 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "Python"
|
|
|
|
|
|
|
|
|
|
```python title="my_list.py"
|
2023-02-06 23:23:21 +08:00
|
|
|
|
[class]{MyList}-[func]{}
|
2022-11-22 17:47:26 +08:00
|
|
|
|
```
|
2022-12-03 01:31:29 +08:00
|
|
|
|
|
|
|
|
|
=== "Go"
|
|
|
|
|
|
|
|
|
|
```go title="my_list.go"
|
2023-02-09 04:45:06 +08:00
|
|
|
|
[class]{myList}-[func]{}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "JavaScript"
|
|
|
|
|
|
2023-02-08 04:27:55 +08:00
|
|
|
|
```javascript title="my_list.js"
|
2023-02-08 19:45:06 +08:00
|
|
|
|
[class]{MyList}-[func]{}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "TypeScript"
|
|
|
|
|
|
|
|
|
|
```typescript title="my_list.ts"
|
2023-02-08 19:45:06 +08:00
|
|
|
|
[class]{MyList}-[func]{}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C"
|
|
|
|
|
|
|
|
|
|
```c title="my_list.c"
|
2023-02-11 18:22:27 +08:00
|
|
|
|
[class]{myList}-[func]{}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
=== "C#"
|
|
|
|
|
|
|
|
|
|
```csharp title="my_list.cs"
|
2023-02-08 22:18:02 +08:00
|
|
|
|
[class]{MyList}-[func]{}
|
2022-12-03 01:31:29 +08:00
|
|
|
|
```
|
2023-01-08 19:41:05 +08:00
|
|
|
|
|
|
|
|
|
=== "Swift"
|
|
|
|
|
|
|
|
|
|
```swift title="my_list.swift"
|
2023-02-08 20:30:05 +08:00
|
|
|
|
[class]{MyList}-[func]{}
|
2023-01-08 23:44:13 +08:00
|
|
|
|
```
|
2023-02-01 22:03:04 +08:00
|
|
|
|
|
|
|
|
|
=== "Zig"
|
|
|
|
|
|
|
|
|
|
```zig title="my_list.zig"
|
2023-02-09 22:57:25 +08:00
|
|
|
|
[class]{MyList}-[func]{}
|
2023-02-01 22:03:04 +08:00
|
|
|
|
```
|