226.翻转二叉树

rust/src/implements/mod.rs

@@ -43,6 +43,7 @@ mod q0198;
 mod q0206;
 mod q0213;
 mod q0220;
+mod q0226;
 mod q0231;
 mod q0258;
 mod q0263;

rust/src/implements/q0226.rs

@@ -0,0 +1,88 @@
+use crate::Solution;
+use std::rc::Rc;
+use std::cell::RefCell;
+use crate::structure::TreeNode;
+
+impl Solution {
+    /// [226.翻转二叉树](https://leetcode-cn.com/problems/invert-binary-tree/)
+    ///
+    /// 2022-02-08 13:35:42
+    ///
+    /// 给你一棵二叉树的根节点 `root` ，翻转这棵二叉树，并返回其根节点。
+    ///
+    /// **示例 1：**
+    ///
+    /// ![](https://assets.leetcode.com/uploads/2021/03/14/invert1-tree.jpg)
+    ///
+    /// **输入：** root = \[4,2,7,1,3,6,9\]
+    /// **输出：** \[4,7,2,9,6,3,1\]
+    ///
+    /// **示例 2：**
+    ///
+    /// ![](https://assets.leetcode.com/uploads/2021/03/14/invert2-tree.jpg)
+    ///
+    /// **输入：** root = \[2,1,3\]
+    /// **输出：** \[2,3,1\]
+    ///
+    /// **示例 3：**
+    ///
+    /// **输入：** root = \[\]
+    /// **输出：** \[\]
+    ///
+    /// **提示：**
+    ///
+    /// *   树中节点数目范围在 `[0, 100]` 内
+    /// *   `-100 <= Node.val <= 100`
+    ///
+    /// Related Topics
+    ///
+    /// *   树
+    /// *   深度优先搜索
+    /// *   广度优先搜索
+    /// *   二叉树
+    ///
+    /// *   👍 1165
+    /// *   👎 0
+    pub fn invert_tree(root: Option<Rc<RefCell<TreeNode>>>) -> Option<Rc<RefCell<TreeNode>>> {
+        match root {
+            Some(node) => {
+                let mut p = node.borrow_mut();
+                Some(Rc::new(RefCell::new(TreeNode { val: p.val, left: Self::invert_tree(p.right.take()), right: Self::invert_tree(p.left.take()) })))
+            }
+            _ => None
+        }
+    }
+}
+
+
+#[cfg(test)]
+mod test {
+    use crate::Solution;
+    use crate::structure::TreeNode;
+    use std::rc::Rc;
+    use std::cell::RefCell;
+
+    #[test]
+    fn test_q0226() {
+        let tree = Some(Rc::new(RefCell::new(TreeNode {
+            val: 1,
+            left: None,
+            right: Some(Rc::new(RefCell::new(TreeNode {
+                val: 2,
+                left: Some(Rc::new(RefCell::new(TreeNode::new(3)))),
+                right: None,
+            }))),
+        })));
+        let tree_inv = Some(Rc::new(RefCell::new(TreeNode {
+            val: 1,
+            left: Some(Rc::new(RefCell::new(TreeNode {
+                val: 2,
+                left: None,
+                right: Some(Rc::new(RefCell::new(TreeNode::new(3)))),
+            }))),
+            right: None,
+        })));
+        let ans = Solution::invert_tree(tree);
+        assert_eq!(ans, tree_inv);
+    }
+}