extern crate rand;

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

fn main() {
    println!("Guess the number!");

    let secret_number = rand::thread_rng().gen_range(1, 101);
    let mut count = 0;

    loop {
        println!("Please input your guess.");

        let mut guess = String::new();

        io::stdin().read_line(&mut guess)
            .expect("Failed to read line");

        let guess: u32 = match guess.trim().parse() {
            Ok(num)     => num,
            Err(_)      => continue,
        };

        count += 1;
        println!("#{}: You guessed: {}", count, guess);

        match guess.cmp(&secret_number) {
            Ordering::Less      => println!("Too small"),
            Ordering::Greater   => println!("Too big"),
            Ordering::Equal     => { 
                println!("You win!!!!");
                println!("Your hit count is {}", count);
                break;
            }
        }
    }
}

• 기본적인 제어 구조와 binding을 이해해야만 작성 가능한
• = 이 '복사'가 아니라 이동이라는 것을 확실히 이해해야 함
• 빌림(borrowing) 개념을 알고 있어야 함