update

exercises/move_semantics/move_semantics1.rs

@@ -3,7 +3,7 @@
 // Execute `rustlings hint move_semantics1` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
+// I AM DONE
 
 #[test]
 fn main() {
@@ -15,9 +15,10 @@ fn main() {
 }
 
 fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
-    let vec = vec;
+    // 可变引用
+    let mut vec = vec;
 
-    vec.push(88);
+    vec.push(88);// push需要改变原变量
 
     vec
 }

exercises/move_semantics/move_semantics2.rs

@@ -5,13 +5,13 @@
 // Execute `rustlings hint move_semantics2` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
+// I AM DONE
 
 #[test]
 fn main() {
     let vec0 = vec![22, 44, 66];
 
-    let mut vec1 = fill_vec(vec0);
+    let mut vec1 = fill_vec(vec0.clone());
 
     assert_eq!(vec0, vec![22, 44, 66]);
     assert_eq!(vec1, vec![22, 44, 66, 88]);

exercises/move_semantics/move_semantics3.rs

@@ -6,7 +6,7 @@
 // Execute `rustlings hint move_semantics3` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
+// I AM DONE
 
 #[test]
 fn main() {
@@ -17,7 +17,7 @@ fn main() {
     assert_eq!(vec1, vec![22, 44, 66, 88]);
 }
 
-fn fill_vec(vec: Vec<i32>) -> Vec<i32> {
+fn fill_vec(mut vec: Vec<i32>) -> Vec<i32> {
     vec.push(88);
 
     vec

exercises/move_semantics/move_semantics4.rs

@@ -7,13 +7,13 @@
 // Execute `rustlings hint move_semantics4` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
+// I AM DONE
 
 #[test]
 fn main() {
     let vec0 = vec![22, 44, 66];
 
-    let mut vec1 = fill_vec(vec0);
+    let mut vec1 = fill_vec();
 
     assert_eq!(vec1, vec![22, 44, 66, 88]);
 }
@@ -21,7 +21,7 @@ fn main() {
 // `fill_vec()` no longer takes `vec: Vec<i32>` as argument - don't change this!
 fn fill_vec() -> Vec<i32> {
     // Instead, let's create and fill the Vec in here - how do you do that?
-    let mut vec = vec;
+    let mut vec = vec![22, 44, 66];
 
     vec.push(88);
 

exercises/move_semantics/move_semantics5.rs

@@ -6,14 +6,16 @@
 // Execute `rustlings hint move_semantics5` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
+// I AM DONE
 
 #[test]
 fn main() {
     let mut x = 100;
     let y = &mut x;
-    let z = &mut x;
     *y += 100;
+    // Mutable borrow can not occur more than twice.
+    let z = &mut x;
+    // *y += 100;
     *z += 1000;
     assert_eq!(x, 1200);
 }

exercises/move_semantics/move_semantics6.rs

@@ -5,24 +5,24 @@
 // Execute `rustlings hint move_semantics6` or use the `hint` watch subcommand
 // for a hint.
 
-// I AM NOT DONE
+// I AM DONE
 
 fn main() {
     let data = "Rust is great!".to_string();
 
-    get_char(data);
+    get_char(&data);
 
-    string_uppercase(&data);
+    string_uppercase(data);
 }
 
 // Should not take ownership
-fn get_char(data: String) -> char {
+fn get_char(data: &String) -> char {
     data.chars().last().unwrap()
 }
 
 // Should take ownership
-fn string_uppercase(mut data: &String) {
+fn string_uppercase(mut data: String) {
-    data = &data.to_uppercase();
+    data = data.to_uppercase();
 
     println!("{}", data);
 }

exercises/vecs/vecs2.rs

@@ -7,7 +7,7 @@
 //
 // Execute `rustlings hint vecs2` or use the `hint` watch subcommand for a hint.
 
-// I AM NOT DONE
+// I AM DONE
 
 fn vec_loop(mut v: Vec<i32>) -> Vec<i32> {
     for element in v.iter_mut() {