#606. Construct String from Binary Tree (C++) - 55ms/24.24% 53.4MB/41.81%

Author: 0x65-e

C++/601-700/606-construct-string-from-binary-tree.cpp

@@ -0,0 +1,35 @@
+//#606. Construct String from Binary Tree (C++) - 55ms/24.24% 53.4MB/41.81%
+/**
+ * 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 {
+public:
+    string tree2str(TreeNode* root) {
+        if (root == nullptr) return "";
+        else {
+            string out;
+            out.append(to_string(root->val));
+            string left = tree2str(root->left);
+            string right = tree2str(root->right);
+            if (left != "" || right != "") {
+                out.push_back('(');
+                out.append(left);
+                out.push_back(')');
+            }
+            if (right != "") {
+                out.push_back('(');
+                out.append(right);
+                out.push_back(')');
+            }
+            return out;
+        }
+    }
+};