From f748e65cb15234612cfd78abbc4926d5292690c5 Mon Sep 17 00:00:00 2001
From: junyoungKim <wnsdud1900427@gmail.com>
Date: Thu, 1 Jan 2026 22:37:13 +0900
Subject: [PATCH 1/3] Reverse Bits

---
 reverse-bits/kimjunyoung90.java | 41 +++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)
 create mode 100644 reverse-bits/kimjunyoung90.java

diff --git a/reverse-bits/kimjunyoung90.java b/reverse-bits/kimjunyoung90.java
new file mode 100644
index 0000000000..286c8f9a7f
--- /dev/null
+++ b/reverse-bits/kimjunyoung90.java
@@ -0,0 +1,41 @@
+class Solution {
+    public int reverseBits(int n) {
+
+        //1. 이진수 변환
+        String binary = toReverseBinary(n);
+
+        //2. 10진수 출력
+        int result = toNumber(binary);
+        return result;
+    }
+
+    private int toNumber(String binary) {
+        int result = 0;
+        for (int i = binary.length(); i > 0 ; i--) {
+            char nChar = binary.charAt(i - 1);
+            result += (nChar == '0' ? 0 : 1) * square(32 - i);
+        }
+        return result;
+    }
+
+    private int square(int i) {
+        int result = 1;
+        for (int j = 0; j < i; j++) {
+            result *= 2;
+        }
+        return result;
+    }
+
+    private String toReverseBinary(int n) {
+        StringBuilder sb = new StringBuilder();
+        while(n > 0) {
+            int remain = n % 2;
+            sb.append(remain);
+            n /= 2;
+        }
+        while(32 >= sb.length()) {
+            sb.append("0");
+        }
+        return sb.toString();
+    }
+}

From 1b5079fa918aa58d9785d5497abd598007d8cfd0 Mon Sep 17 00:00:00 2001
From: junyoungKim <wnsdud1900427@gmail.com>
Date: Thu, 1 Jan 2026 22:56:45 +0900
Subject: [PATCH 2/3] =?UTF-8?q?Reverse=20Bits=20=EA=B0=9C=EC=84=A0?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 reverse-bits/kimjunyoung90.java | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/reverse-bits/kimjunyoung90.java b/reverse-bits/kimjunyoung90.java
index 286c8f9a7f..91e8e23c92 100644
--- a/reverse-bits/kimjunyoung90.java
+++ b/reverse-bits/kimjunyoung90.java
@@ -28,14 +28,10 @@ private int square(int i) {
 
     private String toReverseBinary(int n) {
         StringBuilder sb = new StringBuilder();
-        while(n > 0) {
-            int remain = n % 2;
-            sb.append(remain);
+        for (int i = 0; i < 32; i++) {
+            sb.append(n % 2);
             n /= 2;
         }
-        while(32 >= sb.length()) {
-            sb.append("0");
-        }
         return sb.toString();
     }
 }

From 2fcbdbb0ebbf56f2fb2d029fe3d4739d15e01a2a Mon Sep 17 00:00:00 2001
From: junyoungKim <wnsdud1900427@gmail.com>
Date: Fri, 2 Jan 2026 22:04:02 +0900
Subject: [PATCH 3/3] =?UTF-8?q?Reverse=20Bits=20=EA=B0=9C=EC=84=A0?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 reverse-bits/kimjunyoung90.java | 38 ++++++++++-----------------------
 1 file changed, 11 insertions(+), 27 deletions(-)

diff --git a/reverse-bits/kimjunyoung90.java b/reverse-bits/kimjunyoung90.java
index 91e8e23c92..1b03515b44 100644
--- a/reverse-bits/kimjunyoung90.java
+++ b/reverse-bits/kimjunyoung90.java
@@ -1,37 +1,21 @@
 class Solution {
     public int reverseBits(int n) {
+        int result = 0;
 
-        //1. 이진수 변환
-        String binary = toReverseBinary(n);
+        for (int i = 0; i < 32; i++) {
+            //1. result 새 비트 공간 확보
+            result = result << 1;
 
-        //2. 10진수 출력
-        int result = toNumber(binary);
-        return result;
-    }
+            //2. n의 마지막 비트 추출
+            int last = (n & 1);
 
-    private int toNumber(String binary) {
-        int result = 0;
-        for (int i = binary.length(); i > 0 ; i--) {
-            char nChar = binary.charAt(i - 1);
-            result += (nChar == '0' ? 0 : 1) * square(32 - i);
-        }
-        return result;
-    }
+            //3. 마지막 비트 result에 추가
+            result = result | last;
 
-    private int square(int i) {
-        int result = 1;
-        for (int j = 0; j < i; j++) {
-            result *= 2;
+            //4. n 계산한 비트 제거
+            n = n >> 1;
         }
-        return result;
-    }
 
-    private String toReverseBinary(int n) {
-        StringBuilder sb = new StringBuilder();
-        for (int i = 0; i < 32; i++) {
-            sb.append(n % 2);
-            n /= 2;
-        }
-        return sb.toString();
+        return result;
     }
 }