diff --git a/insert-interval/wogha95.js b/insert-interval/wogha95.js
new file mode 100644
index 000000000..c97e40158
--- /dev/null
+++ b/insert-interval/wogha95.js
@@ -0,0 +1,63 @@
+/**
+ * TC: O(N)
+ * 1번에서 N만큼 순회
+ * 2번에서 최대 N만큼 순회
+ *
+ * SC: O(1)
+ * 겹치는 interval의 시작, 끝 index를 저장하는 변수만 사용
+ *
+ * N: intervals.length
+ */
+
+/**
+ * @param {number[][]} intervals
+ * @param {number[]} newInterval
+ * @return {number[][]}
+ */
+var insert = function (intervals, newInterval) {
+  if (intervals.length === 0) {
+    return [newInterval];
+  }
+  if (newInterval[1] < intervals[0][0]) {
+    return [newInterval, ...intervals];
+  }
+  if (intervals[intervals.length - 1][1] < newInterval[0]) {
+    return [...intervals, newInterval];
+  }
+
+  // 1. 겹치는 interval의 시작, 끝 index를 구한다.
+  let overLappingStartIndex = intervals.length - 1;
+  let overLappingEndIndex = 0;
+  for (let index = 0; index < intervals.length; index++) {
+    const interval = intervals[index];
+    if (newInterval[0] <= interval[1]) {
+      overLappingStartIndex = Math.min(overLappingStartIndex, index);
+    }
+    if (interval[0] <= newInterval[1]) {
+      overLappingEndIndex = Math.max(overLappingEndIndex, index);
+    }
+  }
+
+  // 2.
+  // 시작index 전까지 모두 추가하고
+  // 시작index, 끝index의 최대 범위 interval을 추가하고
+  // 끝index 이후 interval을 모두 추가한다.
+  const result = [];
+  for (let index = 0; index < overLappingStartIndex; index++) {
+    result.push(intervals[index]);
+  }
+  const overLappedStart = Math.min(
+    intervals[overLappingStartIndex][0],
+    newInterval[0]
+  );
+  const overLappedEnd = Math.max(
+    intervals[overLappingEndIndex][1],
+    newInterval[1]
+  );
+  result.push([overLappedStart, overLappedEnd]);
+  for (let index = overLappingEndIndex + 1; index < intervals.length; index++) {
+    result.push(intervals[index]);
+  }
+
+  return result;
+};
diff --git a/maximum-depth-of-binary-tree/wogha95.js b/maximum-depth-of-binary-tree/wogha95.js
new file mode 100644
index 000000000..987cce601
--- /dev/null
+++ b/maximum-depth-of-binary-tree/wogha95.js
@@ -0,0 +1,46 @@
+/**
+ * TC: O(N)
+ * 모든 노드를 순회합니다.
+ *
+ * SC: O(N)
+ * 노드의 수에 비례해서 queue의 길이가 증가됩니다.
+ *
+ * N: count of tree node
+ */
+
+/**
+ * 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 {number}
+ */
+var maxDepth = function (root) {
+  let maximumDepth = 0;
+
+  const queue = [[root, 1]];
+  while (queue.length > 0) {
+    const [current, depth] = queue.shift();
+
+    if (current === null) {
+      break;
+    }
+
+    maximumDepth = Math.max(maximumDepth, depth);
+
+    if (current.left) {
+      queue.push([current.left, depth + 1]);
+    }
+
+    if (current.right) {
+      queue.push([current.right, depth + 1]);
+    }
+  }
+
+  return maximumDepth;
+};
diff --git a/reorder-list/wogha95.js b/reorder-list/wogha95.js
new file mode 100644
index 000000000..1d293b271
--- /dev/null
+++ b/reorder-list/wogha95.js
@@ -0,0 +1,56 @@
+/**
+ * TC: O(N)
+ * 1번에서 절반 길이만큼 순회
+ * 2번에서 절반 길이만큼 순회
+ * 3번에서 절반 길이만큼 순회
+ *
+ * SC: O(1)
+ * linked list의 node를 가리키는 포인터를 가지고 활용하므로 linked list의 길이와 무관한 공간 복잡도를 갖습니다.
+ *
+ * N: linked list length
+ */
+
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} head
+ * @return {void} Do not return anything, modify head in-place instead.
+ */
+var reorderList = function (head) {
+  // 1. linked list 절반 위치 구하기
+  let slow = head;
+  let fast = head;
+
+  while (fast && fast.next) {
+    slow = slow.next;
+    fast = fast.next.next;
+  }
+
+  // 2. 후반 linked list 순서 뒤집기
+  let halfStartTemp = slow.next;
+  let halfStart = null;
+  // 절반을 기준으로 linked list 끊기
+  slow.next = null;
+
+  while (halfStartTemp) {
+    const temp = halfStartTemp.next;
+    halfStartTemp.next = halfStart;
+    halfStart = halfStartTemp;
+    halfStartTemp = temp;
+  }
+
+  // 3. 두 리스트 합치기
+  while (head && halfStart) {
+    const headTemp = head.next;
+    const halfStartTemp = halfStart.next;
+    head.next = halfStart;
+    halfStart.next = headTemp;
+    head = headTemp;
+    halfStart = halfStartTemp;
+  }
+};