Rust IO reading numbers from stdin

1

Hi. What is the best way to do something like this

int a, b;
std::cin >> a >> b;

in rust?
This is my current solution

let mut s = String::new();
io::stdin()
   .read_line(&mut s)
   .unwrap();

let (a,b ): (i32, i32) = {
    let x: Vec<_> = s.trim().split(' ').collect();
    (x[0].parse().unwrap(), x[1].parse().unwrap())
};

This is for competetive programming so all the data is correct.

2

Is your goal to do this efficiently or to do this with minimal boilerplate you have to write? Because, for efficiency, the Vec should be eliminated, but that will require writing a bit more code.

3

minimal boilerplate

4

Well, then, here's a way to get the numbers without repeating .parse().unwrap() for each one, if they are all i32s.

let x: Vec<i32> = s.trim().split(' ').map(|s| s.parse().unwrap()).collect();
let [a, b] = *x else { panic!() };

Ordinarily I would recommend Itertools::collect_array but presumably you are not allowed to use additional libraries.

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