Calculator

---

examples/advanced-functions/calculator/src/main.rs

fn add(x: i32, y: i32) -> i32 {
    x + y
}

fn multiply(x: i32, y: i32) -> i32 {
    x * y
}


fn main() {
    let table: HashMap<String, fn(i32, i32) = 

    let op = "+";

}