structNode{elem: i32,next: Option<Box<Node>>,}fna(){letmutnode=Node{elem: 5,next: None,};letmutsrc=&mutnode;{src};src.next=None;//~ ERROR use of moved value: `src` [E0382]}fnb(){letmutsrc=&mut(22,44);{src};src.0=66;//~ ERROR use of moved value: `src` [E0382]}fnmain(){a();b();}