diff --git a/invert-binary-tree/robinyoon-dev.js b/invert-binary-tree/robinyoon-dev.js
new file mode 100644
index 0000000000..e386e65b8f
--- /dev/null
+++ b/invert-binary-tree/robinyoon-dev.js
@@ -0,0 +1,36 @@
+/**
+ * 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 {TreeNode}
+ */
+var invertTree = function (root) {
+
+    let node = root;
+
+    let result = changeLeftAndRight(node);
+
+    return result;
+
+    function changeLeftAndRight(root) {
+        // 종료 조건
+        if (root === null) return root;
+
+        tempLeft = root.left;
+        tempRight = root.right;
+
+        root.left = tempRight;
+        root.right = tempLeft;
+
+        changeLeftAndRight(root.left);
+        changeLeftAndRight(root.right);
+
+        return root;
+    }
+};
diff --git a/search-in-rotated-sorted-array/robinyoon-dev.js b/search-in-rotated-sorted-array/robinyoon-dev.js
new file mode 100644
index 0000000000..6c4cbc54c0
--- /dev/null
+++ b/search-in-rotated-sorted-array/robinyoon-dev.js
@@ -0,0 +1,16 @@
+/**
+ * @param {number[]} nums
+ * @param {number} target
+ * @return {number}
+ */
+var search = function(nums, target) {
+    let targetIndex = -1;
+
+    for(let i = 0; i < nums.length; i++){
+        if(nums[i] === target){
+            targetIndex = i;
+            break;
+        }
+    }
+    return targetIndex;
+};