use std::collections::HashMap;


pub fn add1(){
    let mut scores = HashMap::new();
    scores.insert(String::from("Blue"),10);
    scores.insert(String::from("Yellow"),50);

}

pub fn get_map(){
    let teams = vec![String::from("Blue"), String::from("Yellow")];
    let initial_scores = vec![10, 50];

    let _scores: HashMap<_, _> =
        teams.into_iter().zip(initial_scores.into_iter()).collect();
}

fn main() {
    use std::collections::HashMap;

    let field_name = String::from("Favorite color");
    let field_value = String::from("Blue");

    let mut map = HashMap::new();
    map.insert(field_name, field_value);
    // field_name and field_value are invalid at this point, try using them and
    // see what compiler error you get!
}

pub fn m1(){
    let mut scores = HashMap::new();
    scores.insert(String::from("Blue"),10);
    scores.insert(String::from("Yellow"),50);

    let team_name = String::from("Blue");
    let score = scores.get(&team_name);

    println!("{:?}",score);

    println!("--------------------------");


    for (key, value) in &scores {
        let val = value + 1;
        println!("{}: {}", key, val);
    }
}

$ cargo run
   Compiling a_map v0.1.0 (/opt/wks/rust/a_map)
    Finished dev [unoptimized + debuginfo] target(s) in 0.28s
     Running `target/debug/a_map`
------------------
Some(10)
--------------------------
Yellow: 51
Blue: 11

//存在就覆盖
pub fn m2(){
    let mut scores = HashMap::new();
    scores.insert(String::from("Blue"),10);
    scores.insert(String::from("Blue"),50);

    let team_name = String::from("Blue");
    let score = scores.get(&team_name);

    println!("{:?}",score);
}

Some(50)

//存在就跳过
pub fn m3(){
    let mut scores = HashMap::new();
    scores.insert(String::from("Blue"),10);
    scores.entry(String::from("Blue")).or_insert(50);

    let team_name = String::from("Blue");
    let score = scores.get(&team_name);

    println!("{:?}",score);
}

Some(10)