rust leetcode interview 32-2

rust-leetcode/README.md

@@ -1180,4 +1180,44 @@ impl Solution {
         start
     }
 }
+```
+* 面试题32 - II. 从上到下打印二叉树 II
+```rust
+impl Solution {
+    //leetcode 102
+    pub fn level_order(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<Vec<i32>> {
+        let mut ret = Vec::new();
+        let mut nodes = VecDeque::new();
+        let mut row = Vec::new();
+        let mut flag = root.clone();
+        nodes.push_back(root.clone());
+        while !nodes.is_empty() {
+            let tmp = nodes.pop_front();
+            if let Some(node) = tmp {
+                if let Some(n) = node {
+                    row.push(n.try_borrow().unwrap().val);
+                    if n.try_borrow().unwrap().left.is_some() {
+                        nodes.push_back(n.try_borrow().unwrap().left.clone());
+                    }
+                    if n.try_borrow().unwrap().right.is_some() {
+                        nodes.push_back(n.try_borrow().unwrap().right.clone());
+                    }
+                    if let Some(f) = flag.borrow() {
+                        if f.as_ptr() == n.as_ptr() {
+                            //直接back导致as_ptr不等
+                            let tail = nodes.pop_back();
+                            if tail.is_some() {
+                                flag = tail.clone().unwrap();
+                                nodes.push_back(tail.unwrap());
+                            }
+                            ret.push(row);
+                            row = Vec::new();
+                        }
+                    }
+                }
+            }
+        }
+        ret
+    }
+}
 ```
\ No newline at end of file

rust-leetcode/src/Solution.rs

@@ -1600,6 +1600,65 @@ fn leetcode_1413() {
     println!("{}", ret)
 }
 
+///从上到下打印二叉树 II
+fn interview_32_2() {
+    println!("interview_32_2");
+    use std::rc::Rc;
+    use std::cell::RefCell;
+    impl Solution {
+        //leetcode 102
+        pub fn level_order(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<Vec<i32>> {
+            let mut ret = Vec::new();
+            let mut nodes = VecDeque::new();
+            let mut row = Vec::new();
+            let mut flag = root.clone();
+            nodes.push_back(root.clone());
+            while !nodes.is_empty() {
+                let tmp = nodes.pop_front();
+                if let Some(node) = tmp {
+                    if let Some(n) = node {
+                        row.push(n.try_borrow().unwrap().val);
+                        if n.try_borrow().unwrap().left.is_some() {
+                            nodes.push_back(n.try_borrow().unwrap().left.clone());
+                        }
+                        if n.try_borrow().unwrap().right.is_some() {
+                            nodes.push_back(n.try_borrow().unwrap().right.clone());
+                        }
+                        if let Some(f) = flag.borrow() {
+                            if f.as_ptr() == n.as_ptr() {
+                                //直接back导致as_ptr不等
+                                let tail = nodes.pop_back();
+                                if tail.is_some() {
+                                    flag = tail.clone().unwrap();
+                                    nodes.push_back(tail.unwrap());
+                                }
+                                ret.push(row);
+                                row = Vec::new();
+                            }
+                        }
+                    }
+                }
+            }
+            ret
+        }
+    }
+
+    let e7 = Some(Rc::new(RefCell::new(TreeNode { val: 7, left: None, right: None })));
+    let e15 = Some(Rc::new(RefCell::new(TreeNode { val: 15, left: None, right: None })));
+    let e20 = Some(Rc::new(RefCell::new(TreeNode { val: 20, left: e15, right: e7 })));
+    let e9 = Some(Rc::new(RefCell::new(TreeNode { val: 9, left: None, right: None })));
+    let e3 = Some(Rc::new(RefCell::new(TreeNode { val: 3, left: e9, right: e20 })));
+//    let e2 = Some(Rc::new(RefCell::new(TreeNode { val: 2, left: None, right: None })));
+//    let e1 = Some(Rc::new(RefCell::new(TreeNode { val: 1, left: e2, right: None })));
+    let ret = Solution::level_order(e3);
+    for v in ret.iter() {
+        for c in v.iter() {
+            print!("{}", c)
+        }
+        println!("\n")
+    }
+}
+
 ///所有方法调用
 pub fn solutions() {
     interview_58_2();
@@ -1651,6 +1710,7 @@ pub fn solutions() {
     leetcode_292();
     leetcode_1160();
     leetcode_1413();
+    interview_32_2();
 }
 
 fn print_vec(nums: Vec<i32>) {