--- a/src/t01guessing/Cargo.toml	Mon Jan 11 16:27:48 2021 +0900
+++ b/src/t01guessing/Cargo.toml	Mon Jan 11 19:17:21 2021 +0900
@@ -7,3 +7,4 @@
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+rand = "0.5.5"
\ No newline at end of file

--- a/src/t01guessing/src/main.rs	Mon Jan 11 16:27:48 2021 +0900
+++ b/src/t01guessing/src/main.rs	Mon Jan 11 19:17:21 2021 +0900
@@ -1,15 +1,37 @@
 use std::io;
+use rand::Rng;
+
+use std::cmp::Ordering;
 
 fn main() {
     println!("Guess the number!");
 
-    println!("Please input your guess.");
+    let secret_number = rand::thread_rng().gen_range(1, 101);
+
+    println!("The secret number is: {}", secret_number);
 
-    let mut guess = String::new();
+    loop {
+        println!("Please input your guess.");
+
+        let mut guess = String::new();
+
+        io::stdin()
+            .read_line(&mut guess)
+            .expect("Failed to read line");
 
-    io::stdin()
-        .read_line(&mut guess)
-        .expect("Failed to read line");
+        let guess: u32 = match guess.trim().parse() {
+            Ok(num) => num,
+            Err(_) => continue,
+        };
+        println!("You guessed: {}", guess);
 
-    println!("You guessed: {}", guess);
-}
+        match guess.cmp(&secret_number) {
+            Ordering::Less => println!("Too small!"),
+            Ordering::Greater => println!("Too big!"),
+            Ordering::Equal => {
+                println!("You win!");
+                break;
+            }
+        }
+    }
+}
\ No newline at end of file