8-17-2020

Author: safrannn

src/_0104_maximum_depth_of_binary_tree.rs

@@ -0,0 +1,31 @@
+struct Solution;
+use crate::util::*;
+use std::cell::RefCell;
+use std::rc::Rc;
+
+impl Solution {
+    pub fn max_depth(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
+        let mut max_depth: i32 = 0;
+        Self::traverse(&root, 1, &mut max_depth);
+        max_depth
+    }
+
+    fn traverse(root: &Option<Rc<RefCell<TreeNode>>>, depth: i32, max_depth: &mut i32) {
+        if let Some(node) = root {
+            if node.borrow().left.is_none() && node.borrow().right.is_none() {
+                if depth > *max_depth {
+                    *max_depth = depth;
+                }
+            }
+            Self::traverse(&node.borrow().left, depth + 1, max_depth);
+            Self::traverse(&node.borrow().right, depth + 1, max_depth);
+        }
+    }
+}
+#[test]
+fn test() {
+    assert_eq!(
+        Solution::max_depth(tree!(3, tree!(9), tree!(20, tree!(15), tree!(7)))),
+        3
+    );
+}

src/_0617_merge_two_binary_trees.rs

@@ -0,0 +1,35 @@
+struct Solution;
+use crate::util::*;
+use std::cell::RefCell;
+use std::rc::Rc;
+impl Solution {
+    pub fn merge_trees(
+        mut t1: Option<Rc<RefCell<TreeNode>>>,
+        mut t2: Option<Rc<RefCell<TreeNode>>>,
+    ) -> Option<Rc<RefCell<TreeNode>>> {
+        Self::helper(&mut t1, &mut t2);
+        t1
+    }
+
+    fn helper(t1: &mut Option<Rc<RefCell<TreeNode>>>, t2: &mut Option<Rc<RefCell<TreeNode>>>) {
+        if t1.is_some() && t2.is_some() {
+            let (mut t1_, mut t2_) = (
+                t1.as_mut().unwrap().borrow_mut(),
+                t2.as_mut().unwrap().borrow_mut(),
+            );
+            t1_.val += t2_.val;
+            Self::helper(&mut t1_.left, &mut t2_.left);
+            Self::helper(&mut t1_.right, &mut t2_.right)
+        } else if t2.is_some() {
+            *t1 = t2.take();
+        }
+    }
+}
+
+#[test]
+fn test() {
+    let t1 = tree!(1, tree!(3, tree!(5), None), tree!(2));
+    let t2 = tree!(2, tree!(1, None, tree!(4)), tree!(3, None, tree!(7)));
+    let res = tree!(3, tree!(4, tree!(5), tree!(4)), tree!(5, None, tree!(7)));
+    assert_eq!(Solution::merge_trees(t1, t2), res);
+}

src/lib.rs

@@ -166,6 +166,8 @@ mod _0561_array_partition_i;
 //
 mod _0605_can_place_flowers;
 //
+mod _0617_merge_two_binary_trees;
+//
 mod _0678_valid_parenthesis_string;
 //
 mod _0680_valid_palindrome_ii;