/** * [129] Sum Root to Leaf Numbers */ pub struct Solution {} use crate::util::tree::{TreeNode, to_tree}; // submission codes start here // Definition for a binary tree node. // #[derive(Debug, PartialEq, Eq)] // pub struct TreeNode { // pub val: i32, // pub left: Option>>, // pub right: Option>>, // } // // impl TreeNode { // #[inline] // pub fn new(val: i32) -> Self { // TreeNode { // val, // left: None, // right: None // } // } // } use std::rc::Rc; use std::cell::RefCell; impl Solution { fn dfs_sum(node: &Rc>, last_num: i32, result: &mut i32) { if node.borrow().left.is_none() && node.borrow().right.is_none() { *result += last_num * 10 + node.borrow().val; } if let Some(left) = &node.borrow().left { Self::dfs_sum(left, last_num * 10 + node.borrow().val, result); } if let Some(right) = &node.borrow().right { Self::dfs_sum(right, last_num * 10 + node.borrow().val, result) } } pub fn sum_numbers(root: Option>>) -> i32 { let mut result = 0; if let Some(root) = root { Self::dfs_sum(&root, 0, &mut result); } result } } // submission codes end #[cfg(test)] mod tests { use super::*; #[test] fn test_129() { } }