Create Sum Root to Leaf Numbers.cpp

Author: daizhenyang

Sum Root to Leaf Numbers.cpp

@@ -0,0 +1,32 @@
+/**
+ * Definition for binary tree
+ * struct TreeNode {
+ *     int val;
+ *     TreeNode *left;
+ *     TreeNode *right;
+ *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
+ * };
+ */
+class Solution {
+public:
+    int ans;
+    void dfs(TreeNode *r,int val)
+    {
+        if (!r)return;
+        if (!r->left&&!r->right)
+        {
+            ans+=val;
+            return;
+        }
+        if (r->left)dfs(r->left,val*10+r->left->val);
+        if (r->right)dfs(r->right,val*10+r->right->val);
+    }
+    int sumNumbers(TreeNode *root) {
+        // Start typing your C/C++ solution below
+        // DO NOT write int main() function
+        if (!root)return 0;
+        ans=0;
+        dfs(root,root->val);
+        return ans;
+    }
+};