Common collections

vector

Doc:https://doc.rust-lang.org/std/vec/struct.Vec.html

more example:https://doc.rust-lang.org/stable/rust-by-example/std/vec.html

fn vec_func() {
    // Creating
    let mut v: Vec<i32> = Vec::new(); // new
    let mut v = vec![1, 2, 3, 4]; // mocro

    // update
    v.push(10);
    v.push(20);
    v.push(30);
    v.push(40);

    // get element
    let v = vec![1, 2, 3, 4, 5];

    let third: &i32 = &v[2];
    println!("The third element is {}", third);

    match v.get(2) {
        Some(third) => println!("The third element is {}", third),
        None => println!("There is no third element."),
    }

    // iterating
    let mut v = vec![100, 32, 57];
    for i in &v { // unmutable
        println!("{}", i);
    }

    for i in &mut v { // mutable
        *i += 50;
    }

    for (i, x) in v.iter().enumerate() { // with index
        println!("In position {} we have value {}", i, x);
    }

    // with enum
    enum SpreadsheetCell {
        Int(i32),
        Float(f64),
        Text(String),
    }

    let row = vec![
        SpreadsheetCell::Int(3),
        SpreadsheetCell::Text(String::from("blue")),
        SpreadsheetCell::Float(10.12),
    ];
}

String

hash map