From 6897c74372e598b76812da93bbf8672b907c5f4a Mon Sep 17 00:00:00 2001
From: juhui <wngml0108@gmail.com>
Date: Sun, 11 Jan 2026 11:55:10 +0900
Subject: [PATCH 1/2] Week 09 Solutions

---
 reverse-bits/juhui-jeong.java | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/reverse-bits/juhui-jeong.java b/reverse-bits/juhui-jeong.java
index 3a8dd1cae..09e0ed9d6 100644
--- a/reverse-bits/juhui-jeong.java
+++ b/reverse-bits/juhui-jeong.java
@@ -3,6 +3,25 @@
  * 공간 복잡도: O(1)
  */
 class Solution {
+    public int reverseBits(int n) {
+        int result = 0;
+
+        for (int i = 0; i < 32; i++) {
+            result = (result << 1) | (n & 1);
+            n >>= 1;
+        }
+        return result;
+    }
+}
+
+/*
+ * 시간 복잡도: O(1)
+ * 공간 복잡도: O(32)
+ * 
+ * 해당 코드로도 동작하지만 문자열 변환 -> 뒤집기 -> 다시 문자열 파싱의 과정을 거치지 않고
+ * 비트를 조작하는 것이 문제의 의도에 더 부합함.
+ *
+class Solution {
 
     public static String toBinaryString(int value) {
         String str = Integer.toBinaryString(value);
@@ -20,3 +39,4 @@ public int reverseBits(int n) {
         return result;
     }
 }
+ */

From b254fbf5fe0fac89789596c913e5a91990ce6d27 Mon Sep 17 00:00:00 2001
From: juhui <wngml0108@gmail.com>
Date: Sun, 11 Jan 2026 11:56:43 +0900
Subject: [PATCH 2/2] add09 Solutions complexity

---
 linked-list-cycle/juhui-jeong.java | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 linked-list-cycle/juhui-jeong.java

diff --git a/linked-list-cycle/juhui-jeong.java b/linked-list-cycle/juhui-jeong.java
new file mode 100644
index 000000000..a890e044d
--- /dev/null
+++ b/linked-list-cycle/juhui-jeong.java
@@ -0,0 +1,17 @@
+/*
+ * 시간 복잡도: O(n)
+ * 공간 복잡도: O(n)
+ */
+public class Solution {
+    public boolean hasCycle(ListNode head) {
+        Set<ListNode> visited = new HashSet<>();
+        while (head != null) {
+            if (visited.contains(head)) {
+                return true;
+            }
+            visited.add(head);
+            head = head.next;
+        }
+        return false;
+    }
+}