add ownership.md

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);
+}
+```
+