Create 0606-construct-string-from-binary-tree.js

Author: aadil42

Diff for: javascript/0606-construct-string-from-binary-tree.js

@@ -0,0 +1,34 @@
+/**
+ * InOrder Traversal 
+ * Time O(n) | Space O(n)
+ * https://leetcode.com/problems/construct-string-from-binary-tree/
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {string}
+ */
+var tree2str = function(root) {
+
+    let str = "";
+    const dfs = (node) => {
+        if(!node) return;
+        str += node.val;
+        if(node.right  || node.left) str += "(";
+        dfs(node.left);
+        if(node.right || node.left) str += ")";
+
+        // right tree
+        if(node.right) str += "(";
+        dfs(node.right);
+        if(node.right) str += ")";
+    }
+
+    dfs(root);
+    return str;
+};