rand number.

src/main.rs

@@ -1,6 +1,11 @@
 use std::io;
+use rand::Rng;
 
 fn main() {
+    let secret_number = rand::thread_rng().gen_range(1..101);
+
+    println!("Secret number is {:?}", secret_number);
+
     println!("Guessing a number:");
 
     let mut guess_number = String::new();