Practical example on Using HashMaps in Rust programming language

Rust HashMaps - With Examples

// Video Tutorial https://youtu.be/nOeOMHtAa2o 
// Youtube Channel: Daily Dose of Rust language
use std::collections::HashMap;

fn main() {
    // How to create Hashmap in Rust.
    let mut student_scores: HashMap<String, f64> = HashMap::new();

    // How to assign values to Hashmaps in Rust.
    student_scores.insert(String::from("Henry"), 100.0);
    student_scores.insert(String::from("John"), 90.0);

    // How to insert a value to Hashmaps in Rust (Only when that value does not exist).
    student_scores.entry(String::from("John")).or_insert(43.0);

    // How to get a value from a hashmap in Rust.
    let henry_score = student_scores
        .get(&String::from("Henry"))
        .copied()
        .unwrap_or(0.0);

    // How to loop through a Hashmap in Rust language.
    for (key, value) in &student_scores {
        println!("key = {}, value = {}", key, value);
    }

    println!("scores = {:?}", student_scores);
    println!("Henry's scores = {:?}", henry_score);
}