From e3d4ee398bb4acaa0da22b3dbc9c41152b2400f6 Mon Sep 17 00:00:00 2001
From: 8804 <8804who@naver.com>
Date: Wed, 18 Feb 2026 15:16:32 +0900
Subject: [PATCH 1/4] Week 15

---
 subtree-of-another-tree/8804who.py | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 subtree-of-another-tree/8804who.py

diff --git a/subtree-of-another-tree/8804who.py b/subtree-of-another-tree/8804who.py
new file mode 100644
index 0000000000..b4b365f73d
--- /dev/null
+++ b/subtree-of-another-tree/8804who.py
@@ -0,0 +1,17 @@
+# Definition for a binary tree node.
+# class TreeNode:
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+class Solution:
+    def isSubtree(self, root: Optional[TreeNode], subRoot: Optional[TreeNode]) -> bool:
+        def getTreeNodes(node):
+            if not node:
+                return "#"
+            
+            return ":"+str(node.val)+":"+getTreeNodes(node.left)+getTreeNodes(node.right)
+
+        
+        return getTreeNodes(subRoot) in getTreeNodes(root)
+    

From 9d2ff8135d7f87f427586dfd5ec2e80737aca792 Mon Sep 17 00:00:00 2001
From: 8804 <8804who@naver.com>
Date: Thu, 19 Feb 2026 21:49:45 +0900
Subject: [PATCH 2/4] Week 15

---
 .../8804who.py                                | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 construct-binary-tree-from-preorder-and-inorder-traversal/8804who.py

diff --git a/construct-binary-tree-from-preorder-and-inorder-traversal/8804who.py b/construct-binary-tree-from-preorder-and-inorder-traversal/8804who.py
new file mode 100644
index 0000000000..b30535b359
--- /dev/null
+++ b/construct-binary-tree-from-preorder-and-inorder-traversal/8804who.py
@@ -0,0 +1,22 @@
+# Definition for a binary tree node.
+# class TreeNode:
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+class Solution:
+    def buildTree(self, preorder: List[int], inorder: List[int]) -> Optional[TreeNode]:
+        inorder_idx = {val:idx for idx, val in enumerate(inorder) }
+        preorder_iter = iter(preorder)
+
+        def dfs(start, end):
+            if start > end:
+                return None
+
+            val = next(preorder_iter)
+            mid = inorder_idx[val]
+
+            return TreeNode(val, dfs(start, mid-1), dfs(mid+1, end))
+        
+        return dfs(0, len(preorder)-1)
+    

From 0d2d7327aa733e28e57845e14188714eab44c580 Mon Sep 17 00:00:00 2001
From: 8804 <8804who@naver.com>
Date: Sat, 21 Feb 2026 00:43:19 +0900
Subject: [PATCH 3/4] Week 15

---
 rotate-image/8804who.py | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 rotate-image/8804who.py

diff --git a/rotate-image/8804who.py b/rotate-image/8804who.py
new file mode 100644
index 0000000000..438e4d6244
--- /dev/null
+++ b/rotate-image/8804who.py
@@ -0,0 +1,37 @@
+from collections import deque
+
+class Solution:
+    def rotate(self, matrix: List[List[int]]) -> None:
+        """
+        Do not return anything, modify matrix in-place instead.
+        """
+
+        def sub(s, e):
+            q = deque()
+
+            for i in range(s, e+1):
+                q.append(matrix[s][i])
+            for i in range(s+1, e+1):
+                q.append(matrix[i][e])
+            for i in range(e-1, s-1, -1):
+                q.append(matrix[e][i])
+            for i in range(e-1, s, -1):
+                q.append(matrix[i][s])
+
+            for _ in range(e-s):
+                q.appendleft(q.pop())
+            
+            for i in range(s, e+1):
+                matrix[s][i] = q.popleft()
+            for i in range(s+1, e+1):
+                matrix[i][e] = q.popleft()
+            for i in range(e-1, s-1, -1):
+                matrix[e][i] = q.popleft()
+            for i in range(e-1, s, -1):
+                matrix[i][s] = q.popleft()
+
+            if s+1 <= e-1:
+                sub(s+1, e-1)
+
+        sub(0, len(matrix)-1)
+    

From 3f74675ff161f68dd73941cec04f3dc54c4622eb Mon Sep 17 00:00:00 2001
From: 8804 <8804who@naver.com>
Date: Sat, 21 Feb 2026 00:43:35 +0900
Subject: [PATCH 4/4] Week 15

---
 longest-palindromic-substring/8804who.py | 28 ++++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 longest-palindromic-substring/8804who.py

diff --git a/longest-palindromic-substring/8804who.py b/longest-palindromic-substring/8804who.py
new file mode 100644
index 0000000000..5502fd8cb8
--- /dev/null
+++ b/longest-palindromic-substring/8804who.py
@@ -0,0 +1,28 @@
+class Solution:
+    def longestPalindrome(self, s: str) -> str:
+        answer = ""
+        for i in range(len(s)):
+            dist = 0
+            temp = ""
+            while i-dist >= 0 and i+dist < len(s):
+                if s[i-dist] == s[i+dist]:
+                    temp = s[i-dist:i+dist+1]
+                    dist+=1
+                else:
+                    break
+            if len(temp) > len(answer):
+                answer = temp
+            if i+1 < len(s):
+                if s[i] != s[i+1]:
+                    continue
+                dist = 0
+                while i-dist >= 0 and i+1+dist < len(s):
+                    if s[i-dist] == s[i+1+dist]:
+                        temp = s[i-dist:i+dist+2]
+                        dist+=1
+                    else:
+                        break
+            if len(temp) > len(answer):
+                answer = temp
+        return answer
+