build

docs/chapter_stack_and_queue/stack.md

@@ -964,16 +964,10 @@ comments: true
         /* 出栈 */
         pub fn pop(&mut self) -> Option<T> {
             self.stack_peek.take().map(|old_head| {
-                match old_head.borrow_mut().next.take() {
-                    Some(new_head) => {
-                        self.stack_peek = Some(new_head);
-                    }
-                    None => {
-                        self.stack_peek = None;
-                    }
-                }
+                self.stack_peek = old_head.borrow_mut().next.take();
                 self.stk_size -= 1;
-                Rc::try_unwrap(old_head).ok().unwrap().into_inner().val
+
+                old_head.borrow().val
             })
         }