feat(leetcode/129): dfs collect

src/leetcode/algorithm_129/README.md

@@ -0,0 +1,3 @@
+Sum Root to Leaf Numbers
+========================
+[leetcode](https://leetcode.com/problems/sum-root-to-leaf-numbers)

src/leetcode/algorithm_129/mod.rs

@@ -0,0 +1,36 @@
+pub struct Solution;
+
+use std::cell::RefCell;
+use std::rc::Rc;
+
+use super::common::TreeNode;
+impl Solution {
+    pub fn dfs_collect(root: Option<Rc<RefCell<TreeNode>>>, mut prefix: Vec<i32>) -> Vec<Vec<i32>> {
+        match root {
+            Some(root) => {
+                prefix.push(root.borrow().val);
+                if root.borrow().right.is_none() && root.borrow().left.is_none() {
+                    return vec![prefix];
+                }
+                let mut left = Self::dfs_collect(root.borrow().left.clone(), prefix.clone());
+                let mut right = Self::dfs_collect(root.borrow().right.clone(), prefix);
+                left.append(&mut right);
+                left
+            }
+            None => vec![],
+        }
+    }
+    pub fn sum_numbers(root: Option<Rc<RefCell<TreeNode>>>) -> i32 {
+        let numbers = Self::dfs_collect(root, vec![]);
+        numbers
+            .into_iter()
+            .flat_map(|digits| {
+                digits
+                    .into_iter()
+                    .rev()
+                    .enumerate()
+                    .map(|(i, n)| n * 10_i32.pow(i as u32))
+            })
+            .sum::<i32>()
+    }
+}

src/leetcode/mod.rs

@@ -9,6 +9,7 @@ pub mod algorithm_12;
 pub mod algorithm_1217;
 pub mod algorithm_124;
 pub mod algorithm_125;
+pub mod algorithm_129;
 pub mod algorithm_1345;
 pub mod algorithm_1413;
 pub mod algorithm_1470;
@@ -23,6 +24,7 @@ pub mod algorithm_198;
 pub mod algorithm_200;
 pub mod algorithm_206;
 pub mod algorithm_2187;
+pub mod algorithm_23;
 pub mod algorithm_2306;
 pub mod algorithm_238;
 pub mod algorithm_2444;
@@ -87,4 +89,3 @@ pub mod unique_binary_search_tree_96;
 pub mod valid_mountain_array_941;
 pub mod valid_parentheses_20;
 pub mod wiggle_subsequence_376;
-pub mod algorithm_23;