reverse_guess.rs

use rand::Rng;
use std::cmp::Ordering;
use std::io;

fn main() {
    println!("Set your secret (1-100):");
    let mut secret = String::new();
    io::stdin()
        .read_line(&mut secret)
        .expect("Failed to read line");

    let secret: u32 = secret.trim().parse().expect("number please!");

    let mut guess = rand::thread_rng().gen_range(1, 101);
    let mut too_low: u32 = 0;
    let mut too_high: u32 = 101;

    loop {
        println!("Computer: I guess {}", guess);

        match guess.cmp(&secret) {
            Ordering::Less => {
                println!("You: too low!");
                too_low = guess;
                guess = rand::thread_rng().gen_range(too_low+1, too_high);
            },
            Ordering::Greater => {
                println!("You: too high!");
                too_high = guess;
                guess = rand::thread_rng().gen_range(too_low+1, too_high);
            },
            Ordering::Equal => {
                println!("You: you win!");
                break;
            },
        }
    }
}