diff --git a/longest-repeating-character-replacement/jylee2033.py b/longest-repeating-character-replacement/jylee2033.py
new file mode 100644
index 000000000..6f9f3f6f1
--- /dev/null
+++ b/longest-repeating-character-replacement/jylee2033.py
@@ -0,0 +1,27 @@
+class Solution:
+    def characterReplacement(self, s: str, k: int) -> int:
+        # "AABABBA", 1
+        # l = 0
+        # r = 4
+        # max_freq = 0
+        # max_len = 4
+        # {"A":1, "B":2}
+
+        l = 0
+        max_len = 0
+        max_freq = 0
+        seen = {}
+
+        for r, char in enumerate(s):
+            seen[char] = seen.get(char, 0) + 1
+            max_freq = max(max_freq, seen[char])
+
+            while (r - l + 1) - max_freq > k:
+                seen[s[l]] -= 1
+                l += 1
+
+            max_len = max(max_len, r - l + 1)
+        return max_len
+
+# Time Complexity: O(n)
+# Space Complexity: O(1)
diff --git a/reverse-bits/jylee2033.py b/reverse-bits/jylee2033.py
new file mode 100644
index 000000000..f2ded7fae
--- /dev/null
+++ b/reverse-bits/jylee2033.py
@@ -0,0 +1,14 @@
+class Solution:
+    def reverseBits(self, n: int) -> int:
+        # 0100
+
+        res = 0
+
+        for _ in range(32):
+            res = (res << 1) | (n & 1)
+            n >>= 1
+
+        return res
+
+# Time Complexity: O(1)
+# Space Complexity: O(1)