Ejercicios 3.1-4

en/src/variables.md

@@ -6,7 +6,7 @@
 
 // Fix the error below with least amount of modification to the code
 fn main() {
-    let x: i32; // Uninitialized but used, ERROR !
+    let x: i32 = 5; // Uninitialized but used, ERROR !
     let y: i32; // Uninitialized but also unused, only a Warning !
 
     assert_eq!(x, 5);
@@ -19,8 +19,8 @@ fn main() {
 
 // Fill the blanks in the code to make it compile
 fn main() {
-    let __ __ = 1;
-    __ += 2; 
+    let mut x = 1;
+    x += 2; 
     
     assert_eq!(x, 3);
     println!("Success!");
@@ -40,6 +40,7 @@ fn main() {
         let y: i32 = 5;
         println!("The value of x is {} and value of y is {}", x, y);
     }
+    let y: i32 = 5;
     println!("The value of x is {} and value of y is {}", x, y); 
 }
 ```
@@ -49,11 +50,12 @@ fn main() {
 
 // Fix the error with the use of define_x
 fn main() {
-    println!("{}, world", x); 
+    let x = define_x();
+    println!("{}, world", x);
 }
 
-fn define_x() {
-    let x = "hello";
+fn define_x() -> String {
+    String::from("hello")
 }
 ```
 

en/src/why-exercise.md

@@ -23,8 +23,9 @@ This book was designed for easily diving into and get skilled with Rust, and it'
 
 We use [mdbook](https://rust-lang.github.io/mdBook/) building our exercises. You can run locally with below steps:
 ```shell
+$ git clone git@github.com:sunface/rust-by-practice.git
 $ cargo install mdbook
-$ cd rust-by-practice && mdbook serve 
+$ cd rust-by-practice && mdbook serve en/ 
 ```
 
 ## Features

zh-CN/src/why-exercise.md

@@ -23,6 +23,7 @@
 
 我们使用 [mdbook](https://rust-lang.github.io/mdBook/) 构建在线练习题，你也可以下载到本地运行：
 ```shell
+$ git clone git@github.com:sunface/rust-by-practice.git
 $ cargo install mdbook
 $ cd rust-by-practice && mdbook serve zh-CN/
 ```