path in binary tree - Facebook

Author: offamitkumar

README.md

@@ -629,3 +629,22 @@
 
 #### Click [__*here*__](Solution/Day-109.cpp) for solution.
 ---
+---
+### Problem 110 
+##### This problem was asked by Facebook.
+##### Given a binary tree, `return all paths from the root to leaves`.
+##### For example, given the tree:
+```
+           1
+          / \
+         2   3
+            / \
+           4   5
+
+```
+##### Return `[[1, 2], [1, 3, 4], [1, 3, 5]]`.
+
+#### Click [__*here*__](Solution/Day-109.cpp) for solution.
+#### Click [__*here*__](https://leetcode.com/problems/binary-tree-paths/) to visit [*LeetCode*](https://leetcode.com/) for this question.
+---
+

Solution/Day-110.cpp

@@ -0,0 +1,35 @@
+/**
+ * Definition for a binary tree node.
+ * struct TreeNode {
+ *     int val;
+ *     TreeNode *left;
+ *     TreeNode *right;
+ *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
+ * };
+ */
+class Solution {
+    vector<string>res;
+    void dfs(TreeNode* root , string path){
+        if(root==nullptr){
+            return;
+        }
+        if(path.size()>0){
+            path+="->";
+        }
+        path+=to_string(root->val);
+        if(root->left == nullptr && root->right == nullptr){
+            res.emplace_back(path);
+            return;
+        }
+        dfs(root->left , path);
+        dfs(root->right , path);
+    }
+public:
+    vector<string> binaryTreePaths(TreeNode* root) {
+        dfs(root , "");
+        return res;
+    }
+};
+