二叉搜索树节点最小距离

智能指针迭代器

  1. use std::rc::Rc;
  2. use std::cell::RefCell;
  3. impl Solution {
  4.     pub fn min_diff_in_bst(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
  5.         fn tile(maybe_node: Option<Rc<RefCell<TreeNode>>>, nums: &mut Vec<i32>) {
  6.             if let Some(node) = maybe_node {
  7.                 tile(node.borrow_mut().left.take(), nums);
  8.                 nums.push(node.borrow().val);
  9.                 tile(node.borrow_mut().right.take(), nums);
  10.             }
  11.         }
  12.         let mut nums = Vec::new();
  13.         tile(root, &mut nums);
  14.         nums.windows(2).map(|x| x[1]-x[0]).min().unwrap_or(0)
  15.     }
  16. }