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< h1 id = "动态数组-vector" > < a class = "header" href = "#动态数组-vector" > 动态数组 Vector< / a > < / h1 >
< p > 动态数组类型用 < code > Vec< T> < / code > 表示，事实上，在之前的章节，它的身影多次出现，我们一直没有细讲，只是简单的把它当作数组处理。< / p >
< p > 动态数组允许你存储多个值，这些值在内存中一个紧挨着另一个排列，因此访问其中某个元素的成本非常低。动态数组只能存储相同类型的元素，如果你想存储不同类型的元素，可以使用之前讲过的枚举类型或者特征对象。< / p >
< p > 总之，当我们想拥有一个列表，里面都是相同类型的数据时，动态数组将会非常有用。< / p >
< h2 id = "创建动态数组" > < a class = "header" href = "#创建动态数组" > 创建动态数组< / a > < / h2 >
< p > 在 Rust 中，有多种方式可以创建动态数组。< / p >
< h3 id = "vecnew" > < a class = "header" href = "#vecnew" > Vec::new< / a > < / h3 >
< p > 使用 < code > Vec::new< / code > 创建动态数组是最 rusty 的方式，它调用了 < code > Vec< / code > 中的 < code > new< / code > 关联函数：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let v: Vec< i32> = Vec::new();
< span class = "boring" > }< / span > < / code > < / pre >
< p > 这里，< code > v< / code > 被显式地声明了类型 < code > Vec< i32> < / code > ，这是因为 Rust 编译器无法从 < code > Vec::new()< / code > 中得到任何关于类型的暗示信息，因此也无法推导出 < code > v< / code > 的具体类型，但是当你向里面增加一个元素后，一切又不同了：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let mut v = Vec::new();
v.push(1);
< span class = "boring" > }< / span > < / code > < / pre >
< p > 此时，< code > v< / code > 就无需手动声明类型，因为编译器通过 < code > v.push(1)< / code > ，推测出 < code > v< / code > 中的元素类型是 < code > i32< / code > ，因此推导出 < code > v< / code > 的类型是 < code > Vec< i32> < / code > 。< / p >
< blockquote >
< p > 如果预先知道要存储的元素个数，可以使用 < code > Vec::with_capacity(capacity)< / code > 创建动态数组，这样可以避免因为插入大量新数据导致频繁的内存分配和拷贝，提升性能< / p >
< / blockquote >
< h3 id = "vec" > < a class = "header" href = "#vec" > vec![]< / a > < / h3 >
< p > 还可以使用宏 < code > vec!< / code > 来创建数组，与 < code > Vec::new< / code > 有所不同，前者能在创建同时给予初始化值：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let v = vec![1, 2, 3];
< span class = "boring" > }< / span > < / code > < / pre >
< p > 同样，此处的 < code > v< / code > 也无需标注类型，编译器只需检查它内部的元素即可自动推导出 < code > v< / code > 的类型是 < code > Vec< i32> < / code > （ < code > i32< / code > ，在< a href = "https://course.rs/basic/base-type/numbers.html#整数类型" > 数值类型< / a > 中有详细介绍）。< / p >
< h2 id = "更新-vector" > < a class = "header" href = "#更新-vector" > 更新 Vector< / a > < / h2 >
< p > 向数组尾部添加元素，可以使用 < code > push< / code > 方法：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let mut v = Vec::new();
v.push(1);
< span class = "boring" > }< / span > < / code > < / pre >
< p > 与其它类型一样，必须将 < code > v< / code > 声明为 < code > mut< / code > 后，才能进行修改。< / p >
< h2 id = "vector-与其元素共存亡" > < a class = "header" href = "#vector-与其元素共存亡" > Vector 与其元素共存亡< / a > < / h2 >
< p > 跟结构体一样，< code > Vector< / code > 类型在超出作用域范围后，会被自动删除：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > {
let v = vec![1, 2, 3];
// ...
} // < - v超出作用域并在此处被删除
< span class = "boring" > }< / span > < / code > < / pre >
< p > 当 < code > Vector< / code > 被删除后，它内部存储的所有内容也会随之被删除。目前来看，这种解决方案简单直白，但是当 < code > Vector< / code > 中的元素被引用后，事情可能会没那么简单。< / p >
< h2 id = "从-vector-中读取元素" > < a class = "header" href = "#从-vector-中读取元素" > 从 Vector 中读取元素< / a > < / h2 >
< p > 读取指定位置的元素有两种方式可选：< / p >
< ul >
< li > 通过下标索引访问。< / li >
< li > 使用 < code > get< / code > 方法。< / li >
< / ul >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let v = vec![1, 2, 3, 4, 5];
let third: & i32 = & v[2];
println!("第三个元素是 {}", third);
match v.get(2) {
Some(third) => println!("第三个元素是 {third}"),
None => println!("去你的第三个元素，根本没有！"),
}
< span class = "boring" > }< / span > < / code > < / pre >
< p > 和其它语言一样，集合类型的索引下标都是从 < code > 0< / code > 开始，< code > & v[2]< / code > 表示借用 < code > v< / code > 中的第三个元素，最终会获得该元素的引用。而 < code > v.get(2)< / code > 也是访问第三个元素，但是有所不同的是，它返回了 < code > Option< & T> < / code > ，因此还需要额外的 < code > match< / code > 来匹配解构出具体的值。< / p >
< blockquote >
< p > 细心的同学会注意到这里使用了两种格式化输出的方式，其中第一种我们在之前已经见过，而第二种是后续新版本中引入的写法，也是更推荐的用法，具体介绍请参见< a href = "https://course.rs/basic/formatted-output.html" > 格式化输出章节< / a > 。< / p >
< / blockquote >
< h3 id = "下标索引与-get-的区别" > < a class = "header" href = "#下标索引与-get-的区别" > 下标索引与 < code > .get< / code > 的区别< / a > < / h3 >
< p > 这两种方式都能成功的读取到指定的数组元素，既然如此为什么会存在两种方法？何况 < code > .get< / code > 还会增加使用复杂度，这就涉及到数组越界的问题了，让我们通过示例说明：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let v = vec![1, 2, 3, 4, 5];
let does_not_exist = & v[100];
let does_not_exist = v.get(100);
< span class = "boring" > }< / span > < / code > < / pre >
< p > 运行以上代码，< code > & v[100]< / code > 的访问方式会导致程序无情报错退出，因为发生了数组越界访问。 但是 < code > v.get< / code > 就不会，它在内部做了处理，有值的时候返回 < code > Some(T)< / code > ，无值的时候返回 < code > None< / code > ，因此 < code > v.get< / code > 的使用方式非常安全。< / p >
< p > 既然如此，为何不统一使用 < code > v.get< / code > 的形式？ ， < / p >
< p > 既然有两个选择，肯定就有如何选择的问题，答案很简单，当你确保索引不会越界的时候，就用索引访问，否则用 < code > .get< / code > 。例如，访问第几个数组元素并不取决于我们，而是取决于用户的输入时，用 < code > .get< / code > 会非常适合，天知道那些可爱的用户会输入一个什么样的数字进来！< / p >
< h2 id = "同时借用多个数组元素" > < a class = "header" href = "#同时借用多个数组元素" > 同时借用多个数组元素< / a > < / h2 >
< p > 既然涉及到借用数组元素，那么很可能会遇到同时借用多个数组元素的情况，还记得在< a href = "https://course.rs/basic/ownership/borrowing.html#借用规则总结" > 所有权和借用< / a > 章节咱们讲过的借用规则嘛？如果记得，就来看看下面的代码 :)< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let mut v = vec![1, 2, 3, 4, 5];
let first = & v[0];
v.push(6);
println!("The first element is: {first}");
< span class = "boring" > }< / span > < / code > < / pre >
< p > 先不运行，来推断下结果，首先 < code > first = & v[0]< / code > 进行了不可变借用，< code > v.push< / code > 进行了可变借用，如果 < code > first< / code > 在 < code > v.push< / code > 之后不再使用，那么该段代码可以成功编译（原因见< a href = "https://course.rs/basic/ownership/borrowing.html#可变引用与不可变引用不能同时存在" > 引用的作用域< / a > ）。< / p >
< p > 可是上面的代码中，< code > first< / code > 这个不可变借用在可变借用 < code > v.push< / code > 后被使用了，那么妥妥的，编译器就会报错：< / p >
< pre > < code class = "language-console" > $ cargo run
Compiling collections v0.1.0 (file:///projects/collections)
error[E0502]: cannot borrow `v` as mutable because it is also borrowed as immutable 无法对v进行可变借用，
--> src/main.rs:6:5
|
4 | let first = & v[0];
| - immutable borrow occurs here // 不可变借用发生在此处
5 |
6 | v.push(6);
| ^^^^^^^^^ mutable borrow occurs here // 可变借用发生在此处
7 |
8 | println!("The first element is: {}", first);
| ----- immutable borrow later used here // 不可变借用在这里被使用
For more information about this error, try `rustc --explain E0502`.
error: could not compile `collections` due to previous error
< / code > < / pre >
< p > 其实，按理来说，这两个引用不应该互相影响的：一个是查询元素，一个是在数组尾部插入元素，完全不相干的操作，为何编译器要这么严格呢？< / p >
< p > 原因在于： ， ， < / p >
< p > 其实想想，< strong > 在长大之后，我们感激人生路上遇到过的严师益友，正是因为他们，我们才在正确的道路上不断前行，虽然在那个时候，并不能理解他们< / strong > ，而 Rust 就如那个良师益友，它不断的在纠正我们不好的编程习惯，直到某一天，你发现自己能写出一次性通过的漂亮代码时，就能明白它的良苦用心。< / p >
< blockquote >
< p > 若读者想要更深入的了解 < code > Vec< T> < / code > ，可以看看< a href = "https://nomicon.purewhite.io/vec/vec.html" > Rustonomicon< / a > ，其中从零手撸一个动态数组，非常适合深入学习。< / p >
< / blockquote >
< h2 id = "迭代遍历-vector-中的元素" > < a class = "header" href = "#迭代遍历-vector-中的元素" > 迭代遍历 Vector 中的元素< / a > < / h2 >
< p > 如果想要依次访问数组中的元素，可以使用迭代的方式去遍历数组，这种方式比用下标的方式去遍历数组更安全也更高效（每次下标访问都会触发数组边界检查）：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let v = vec![1, 2, 3];
for i in & v {
println!("{i}");
}
< span class = "boring" > }< / span > < / code > < / pre >
< p > 也可以在迭代过程中，修改 < code > Vector< / code > 中的元素：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let mut v = vec![1, 2, 3];
for i in & mut v {
*i += 10
}
< span class = "boring" > }< / span > < / code > < / pre >
< h2 id = "存储不同类型的元素" > < a class = "header" href = "#存储不同类型的元素" > 存储不同类型的元素< / a > < / h2 >
< p > 在本节开头，有讲到数组的元素必须类型相同，但是也提到了解决方案：那就是通过使用枚举类型和特征对象来实现不同类型元素的存储。先来看看通过枚举如何实现：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > #[derive(Debug)]
enum IpAddr {
V4(String),
V6(String)
}
fn main() {
let v = vec![
IpAddr::V4("127.0.0.1".to_string()),
IpAddr::V6("::1".to_string())
];
for ip in v {
show_addr(ip)
}
}
fn show_addr(ip: IpAddr) {
println!("{:?}",ip);
}< / code > < / pre >
< p > 数组 < code > v< / code > 中存储了两种不同的 < code > ip< / code > 地址，但是这两种都属于 < code > IpAddr< / code > 枚举类型的成员，因此可以存储在数组中。< / p >
< p > 再来看看特征对象的实现：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > trait IpAddr {
fn display(& self);
}
struct V4(String);
impl IpAddr for V4 {
fn display(& self) {
println!("ipv4: {:?}",self.0)
}
}
struct V6(String);
impl IpAddr for V6 {
fn display(& self) {
println!("ipv6: {:?}",self.0)
}
}
fn main() {
let v: Vec< Box< dyn IpAddr> > = vec![
Box::new(V4("127.0.0.1".to_string())),
Box::new(V6("::1".to_string())),
];
for ip in v {
ip.display();
}
}< / code > < / pre >
< p > 比枚举实现要稍微复杂一些，我们为 < code > V4< / code > 和 < code > V6< / code > 都实现了特征 < code > IpAddr< / code > ，然后将它俩的实例用 < code > Box::new< / code > 包裹后，存在了数组 < code > v< / code > 中，需要注意的是，这里必须手动地指定类型：< code > Vec< Box< dyn IpAddr> > < / code > ，表示数组 < code > v< / code > 存储的是特征 < code > IpAddr< / code > 的对象，这样就实现了在数组中存储不同的类型。< / p >
< p > 在实际使用场景中，< strong > 特征对象数组要比枚举数组常见很多< / strong > ，主要原因在于< a href = "https://course.rs/basic/trait/trait-object.html" > 特征对象< / a > 非常灵活，而编译器对枚举的限制较多，且无法动态增加类型。< / p >
< h2 id = "vector-常用方法" > < a class = "header" href = "#vector-常用方法" > Vector 常用方法< / a > < / h2 >
< p > 初始化 vec 的更多方式：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > fn main() {
let v = vec![0; 3]; // 默认值为 0，
let v_from = Vec::from([0, 0, 0]);
assert_eq!(v, v_from);
}< / code > < / pre >
< p > 动态数组意味着我们增加元素时，如果< strong > 容量不足就会导致 vector 扩容< / strong > （目前的策略是重新申请一块 2 倍大小的内存，再将所有元素拷贝到新的内存位置，同时更新指针数据），显然，当频繁扩容或者当元素数量较多且需要扩容时，大量的内存拷贝会降低程序的性能。< / p >
< p > 可以考虑在初始化时就指定一个实际的预估容量，尽量减少可能的内存拷贝：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > fn main() {
let mut v = Vec::with_capacity(10);
v.extend([1, 2, 3]); // 附加数据到 v
println!("Vector 长度是: {}, 容量是: {}", v.len(), v.capacity());
v.reserve(100); // 调整 v 的容量，至少要有 100 的容量
println!("Vector（ ）
v.shrink_to_fit(); // 释放剩余的容量，一般情况下，不会主动去释放容量
println!("Vector（ ）
}< / code > < / pre >
< p > Vector 常见的一些方法示例：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > #![allow(unused)]
< / span > < span class = "boring" > fn main() {
< / span > let mut v = vec![1, 2];
assert!(!v.is_empty()); // 检查 v 是否为空
v.insert(2, 3); // 在指定索引插入数据，索引值不能大于 v 的长度， v: [1, 2, 3]
assert_eq!(v.remove(1), 2); // 移除指定位置的元素并返回, v: [1, 3]
assert_eq!(v.pop(), Some(3)); // 删除并返回 v 尾部的元素，
assert_eq!(v.pop(), Some(1)); // v: []
assert_eq!(v.pop(), None); // 记得 pop 方法返回的是 Option 枚举值
v.clear(); // 清空 v, v: []
let mut v1 = [11, 22].to_vec(); // append 操作会导致 v1 清空数据，增加可变声明
v.append(& mut v1); // 将 v1 中的所有元素附加到 v 中, v1: []
v.truncate(1); // 截断到指定长度，多余的元素被删除, v: [11]
v.retain(|x| *x > 10); // 保留满足条件的元素，即删除不满足条件的元素
let mut v = vec![11, 22, 33, 44, 55];
// 删除指定范围的元素，同时获取被删除元素的迭代器, v: [11, 55], m: [22, 33, 44]
let mut m: Vec< _> = v.drain(1..=3).collect();
let v2 = m.split_off(1); // 指定索引处切分成两个 vec, m: [22], v2: [33, 44]
< span class = "boring" > }< / span > < / code > < / pre >
< p > 当然也可以像< a href = "/basic/compound-type/array.html#数组切片" > 数组切片< / a > 的方式获取 vec 的部分元素：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > fn main() {
let v = vec![11, 22, 33, 44, 55];
let slice = & v[1..=3];
assert_eq!(slice, & [22, 33, 44]);
}< / code > < / pre >
< p > 更多细节，阅读 Vector 的< a href = "https://doc.rust-lang.org/std/vec/struct.Vec.html#" > 标准库文档< / a > 。< / p >
< h2 id = "vector-的排序" > < a class = "header" href = "#vector-的排序" > Vector 的排序< / a > < / h2 >
< p > 在 rust 里，实现了两种排序算法，分别为稳定的排序 < code > sort< / code > 和 < code > sort_by< / code > ，以及非稳定排序 < code > sort_unstable< / code > 和 < code > sort_unstable_by< / code > 。< / p >
< p > 当然，这个所谓的 < code > 非稳定< / code > 并不是指排序算法本身不稳定，而是指在排序过程中对相等元素的处理方式。在 < code > 稳定< / code > 排序算法里，对相等的元素，不会对其进行重新排序。而在 < code > 不稳定< / code > 的算法里则不保证这点。< / p >
< p > 总体而言，< code > 非稳定< / code > 排序的算法的速度会优于 < code > 稳定< / code > 排序算法，同时，< code > 稳定< / code > 排序还会额外分配原数组一半的空间。< / p >
< h3 id = "整数数组的排序" > < a class = "header" href = "#整数数组的排序" > 整数数组的排序< / a > < / h3 >
< p > 以下是对整数列进行排序的例子。< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > fn main() {
let mut vec = vec![1, 5, 10, 2, 15];
vec.sort_unstable();
assert_eq!(vec, vec![1, 2, 5, 10, 15]);
}< / code > < / pre >
< h3 id = "浮点数数组的排序" > < a class = "header" href = "#浮点数数组的排序" > 浮点数数组的排序< / a > < / h3 >
< p > 我们尝试使用上面的方法来对浮点数进行排序：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > fn main() {
let mut vec = vec![1.0, 5.6, 10.3, 2.0, 15f32];
vec.sort_unstable();
assert_eq!(vec, vec![1.0, 2.0, 5.6, 10.3, 15f32]);
}< / code > < / pre >
< p > 结果，居然报错了，< / p >
< pre > < code > error[E0277]: the trait bound `f32: Ord` is not satisfied
--> src/main.rs:29:13
|
29 | vec.sort_unstable();
| ^^^^^^^^^^^^^ the trait `Ord` is not implemented for `f32`
|
= help: the following other types implement trait `Ord`:
i128
i16
i32
i64
i8
isize
u128
u16
and 4 others
note: required by a bound in `core::slice::< impl [T]> ::sort_unstable`
--> /home/keijack/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/slice/mod.rs:2635:12
|
2635 | T: Ord,
| ^^^ required by this bound in `core::slice::< impl [T]> ::sort_unstable`
For more information about this error, try `rustc --explain E0277`.
< / code > < / pre >
< p > 原来，在浮点数当中，存在一个 < code > NAN< / code > 的值，这个值无法与其他的浮点数进行对比，因此，浮点数类型并没有实现全数值可比较 < code > Ord< / code > 的特性，而是实现了部分可比较的特性 < code > PartialOrd< / code > 。< / p >
< p > 如此，如果我们确定在我们的浮点数数组当中，不包含 < code > NAN< / code > 值，那么我们可以使用 < code > partial_cmp< / code > 来作为大小判断的依据。< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > fn main() {
let mut vec = vec![1.0, 5.6, 10.3, 2.0, 15f32];
vec.sort_unstable_by(|a, b| a.partial_cmp(b).unwrap());
assert_eq!(vec, vec![1.0, 2.0, 5.6, 10.3, 15f32]);
}< / code > < / pre >
< p > OK， < / p >
< h3 id = "对结构体数组进行排序" > < a class = "header" href = "#对结构体数组进行排序" > 对结构体数组进行排序< / a > < / h3 >
< p > 有了上述浮点数排序的经验，我们推而广之，那么对结构体是否也可以使用这种自定义对比函数的方式来进行呢？马上来试一下：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > #[derive(Debug)]
struct Person {
name: String,
age: u32,
}
impl Person {
fn new(name: String, age: u32) -> Person {
Person { name, age }
}
}
fn main() {
let mut people = vec![
Person::new("Zoe".to_string(), 25),
Person::new("Al".to_string(), 60),
Person::new("John".to_string(), 1),
];
// 定义一个按照年龄倒序排序的对比函数
people.sort_unstable_by(|a, b| b.age.cmp(& a.age));
println!("{:?}", people);
}< / code > < / pre >
< p > 执行后输出：< / p >
< pre > < code > [Person { name: "Al", age: 60 }, Person { name: "Zoe", age: 25 }, Person { name: "John", age: 1 }]
< / code > < / pre >
< p > 结果正确。< / p >
< p > 从上面我们学习过程当中，排序需要我们实现 < code > Ord< / code > 特性，那么如果我们把我们的结构体实现了该特性，是否就不需要我们自定义对比函数了呢？< / p >
< p > 是，但不完全是，实现 < code > Ord< / code > 需要我们实现 < code > Ord< / code > 、< code > Eq< / code > 、< code > PartialEq< / code > 、< code > PartialOrd< / code > 这些属性。好消息是，你可以 < code > derive< / code > 这些属性：< / p >
< pre class = "playground" > < code class = "language-rust edition2021" > #[derive(Debug, Ord, Eq, PartialEq, PartialOrd)]
struct Person {
name: String,
age: u32,
}
impl Person {
fn new(name: String, age: u32) -> Person {
Person { name, age }
}
}
fn main() {
let mut people = vec![
Person::new("Zoe".to_string(), 25),
Person::new("Al".to_string(), 60),
Person::new("Al".to_string(), 30),
Person::new("John".to_string(), 1),
Person::new("John".to_string(), 25),
];
people.sort_unstable();
println!("{:?}", people);
}< / code > < / pre >
< p > 执行输出< / p >
< pre > < code > [Person { name: "Al", age: 30 }, Person { name: "Al", age: 60 }, Person { name: "John", age: 1 }, Person { name: "John", age: 25 }, Person { name: "Zoe", age: 25 }]
< / code > < / pre >
< p > 需要 < code > derive< / code > < code > Ord< / code > 相关特性，需要确保你的结构体中所有的属性均实现了 < code > Ord< / code > 相关特性，否则会发生编译错误。< code > derive< / code > 的默认实现会依据属性的顺序依次进行比较，如上述例子中，当 < code > Person< / code > 的 < code > name< / code > 值相同，则会使用 < code > age< / code > 进行比较。< / p >
< h2 id = "课后练习" > < a class = "header" href = "#课后练习" > 课后练习< / a > < / h2 >
< blockquote >
< p > < a href = "https://practice-zh.course.rs/collections/vector.html" > Rust By Practice< / a > ，支持代码在线编辑和运行，并提供详细的< a href = "https://github.com/sunface/rust-by-practice/blob/master/solutions/collections/Vector.md" > 习题解答< / a > 。< / p >
< / blockquote >
< / main >
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