main.rs

use std::io;

fn get_guess() -> i32 {
    let mut guess = String::new();
    io::stdin()
        .read_line(&mut guess)
        .expect("Failure reading input.");

    match guess.trim().parse::<i32>() {
        Ok(number) => number,
        Err(_) => {
            println!("Please enter a valid number.");
            return get_guess();
        }
    }
}

fn main() {
    println!("Try guessing the secret number:");
    let guess = get_guess();
    println!("You guessed {}", guess);
}