Code shared from the Rust Playground

playground.rs

use std::collections::HashMap;
use std::str;
fn main() {
    let s = "a, 100\nb, 200\nw, 20";
    let mut m = HashMap::new();
    s.split('\n').map(|line| {
        let v: Vec<_>= line.split(',').map(str::trim).collect();
        println!("{:?}", v);
        if v.len() == 2 {
            m.insert(v[0], v[1]);
        }
    }).collect();
    println!("{:?}", m);
}