From acf90533c18a23a1b2bbe0f1babecc6fdc8fd00a Mon Sep 17 00:00:00 2001
From: sadie100 <03sadie@gmail.com>
Date: Tue, 21 Apr 2026 21:18:11 +0900
Subject: [PATCH 1/3] sadie100: reverse bits solution

---
 reverse-bits/sadie100.ts | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 reverse-bits/sadie100.ts

diff --git a/reverse-bits/sadie100.ts b/reverse-bits/sadie100.ts
new file mode 100644
index 0000000000..82717769e6
--- /dev/null
+++ b/reverse-bits/sadie100.ts
@@ -0,0 +1,19 @@
+/**
+ n의 뒤의 자리에서부터 비트로 변환해서 result에 붙이고, result 비트를 앞으로 당기는 일을 32번 반복해서 뒤집어진 비트를 만든다
+
+ 시간복잡도 : O(1) - 비트 연산
+ 공간복잡도 : O(1)
+ */
+
+function reverseBits(n: number): number {
+  let result = 0
+
+  for (let i = 0; i < 32; i++) {
+    let bit = n & 1
+
+    result = (result << 1) | bit
+
+    n = n >>> 1
+  }
+  return result >>> 0
+}

From 4b29af85b4548deb7f0156b8835ef95a4acb77fa Mon Sep 17 00:00:00 2001
From: Se Hee Kim <82367039+sadie100@users.noreply.github.com>
Date: Thu, 23 Apr 2026 12:48:44 +0900
Subject: [PATCH 2/3] Update reverse-bits/sadie100.ts

Co-authored-by: Dale Seo <5466341+DaleSeo@users.noreply.github.com>
---
 reverse-bits/sadie100.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/reverse-bits/sadie100.ts b/reverse-bits/sadie100.ts
index 82717769e6..f079c8c382 100644
--- a/reverse-bits/sadie100.ts
+++ b/reverse-bits/sadie100.ts
@@ -9,7 +9,7 @@ function reverseBits(n: number): number {
   let result = 0
 
   for (let i = 0; i < 32; i++) {
-    let bit = n & 1
+    const bit = n & 1
 
     result = (result << 1) | bit
 

From a0a5139d5d02c28aa88124c444019bcb1283d85d Mon Sep 17 00:00:00 2001
From: sadie100 <03sadie@gmail.com>
Date: Sun, 26 Apr 2026 01:46:27 +0900
Subject: [PATCH 3/3] sadie100: longest repeating character solution

---
 .../sadie100.ts                               | 34 +++++++++++++++++++
 1 file changed, 34 insertions(+)
 create mode 100644 longest-repeating-character-replacement/sadie100.ts

diff --git a/longest-repeating-character-replacement/sadie100.ts b/longest-repeating-character-replacement/sadie100.ts
new file mode 100644
index 0000000000..9017f2cd06
--- /dev/null
+++ b/longest-repeating-character-replacement/sadie100.ts
@@ -0,0 +1,34 @@
+/*
+start, end 투 포인터 변수를 생성하고 end를 하나씩 늘려 가며 s를 탐색
+글자별 개수를 저장하는 map, 최빈 등장수 maxCount를 통해 가장 많이 나온 캐릭터의 카운트를 저장하고
+만약 end-start+1-maxCount가 k를 넘어가면 start를 +1한다
+매번 end-start+1와 현 result를 비교하여 큰 값을 result로 갱신한다
+
+시간복잡도 : O(N)
+*/
+
+function characterReplacement(s: string, k: number): number {
+  let start = 0
+  let end = 0
+  let result = 0
+  let maxCount = 0
+  const charMap = new Map()
+
+  while (end < s.length) {
+    const thisChar = s[end]
+    const updatedCount = (charMap.get(thisChar) || 0) + 1
+    charMap.set(thisChar, updatedCount)
+    maxCount = Math.max(maxCount, updatedCount)
+
+    if (end - start + 1 - maxCount > k) {
+      const startChar = s[start]
+      charMap.set(startChar, charMap.get(startChar) - 1)
+      start += 1
+    }
+
+    result = Math.max(result, end - start + 1)
+    end += 1
+  }
+
+  return result
+}