add ownership.md

en/src/SUMMARY.md

@@ -7,7 +7,7 @@
   - [Char, Bool and Unit](basic-types/char-bool-unit.md)
   - [Statements and Expressions](basic-types/statements-expressions.md)
   - [Functions](basic-types/functions.md)
-- [Ownership and Borrowing todo](ownership/intro.md)
+- [Ownership and Borrowing](ownership/intro.md)
   - [Ownership](ownership/ownership.md)
   - [Reference and Borrowing](ownership/borrowing.md)
 - [Compound Types todo](compound-types/intro.md)

en/src/ownership/intro.md

@@ -1 +1,5 @@
 # Ownership and Borrowing
+Learning resources: 
+- English: [Rust Book 4.1-4.4](https://doc.rust-lang.org/book/ch04-00-understanding-ownership.html)
+- 简体中文: [Rust语言圣经 - 所有权与借用(https://course.rs/basic/ownership/index.html)
+

en/src/ownership/ownership.md

@@ -1 +1,73 @@
 # Ownership
+
+🌟🌟
+```rust,editable
+
+fn main() {
+    // modify this line only! use as many approaches as you can
+    let x = String::from("hello, world");
+    let y = x;
+    println!("{},{}",x,y);
+}
+```
+
+🌟🌟
+```rust,editable
+// Don't modify code in main!
+fn main() {
+    let s1 = String::from("hello, world");
+    let s2 = take_ownership(s1);
+
+    println!("{}", s2);
+}
+
+// Only modify the code below!
+fn take_ownership(s: String) {
+    println!("{}", s);
+}
+```
+
+
+🌟🌟
+```rust,editable
+
+fn main() {
+    let s = give_ownership();
+    println!("{}", s);
+}
+
+// Only modify the code below!
+fn give_ownership() -> String {
+    let s = String::from("hello, world");
+    // convert String to Vec
+    let _s = s.into_bytes();
+    s
+}
+```
+
+🌟🌟
+```rust,editable
+// use clone to fix it
+fn main() {
+    let s = String::from("hello, world");
+
+    print_str(s);
+
+    println!("{}", s);
+}
+
+fn print_str(s: String)  {
+    println!("{}",s)
+}
+```
+
+🌟🌟 
+```rust, editable
+// don't use clone ,use copy instead
+fn main() {
+    let x = (1, 2, (), "hello");
+    let y = x.clone();
+    println!("{:?}, {:?}", x, y);
+}
+```
+