diff --git a/3sum/mrlee7.py b/3sum/mrlee7.py
new file mode 100644
index 000000000..d84f6a902
--- /dev/null
+++ b/3sum/mrlee7.py
@@ -0,0 +1,34 @@
+from typing import List
+
+
+class Solution:
+    def threeSum(self, nums: List[int]) -> List[List[int]]:
+        result: List[List[int]] = []
+        nums.sort()
+
+        for i in range(len(nums) - 2):
+            if i > 0 and nums[i] == nums[i - 1]:
+                continue
+
+            left = i + 1
+            right = len(nums) - 1
+
+            while left < right:
+                total = nums[i] + nums[left] + nums[right]
+
+                if total == 0:
+                    result.append([nums[i], nums[left], nums[right]])
+                    left += 1
+                    right -= 1
+
+                    while left < right and nums[left] == nums[left - 1]:
+                        left += 1
+                    while left < right and nums[right] == nums[right + 1]:
+                        right -= 1
+
+                elif total < 0:
+                    left += 1
+                else:
+                    right -= 1
+
+        return result
diff --git a/climbing-stairs/mrlee7.py b/climbing-stairs/mrlee7.py
new file mode 100644
index 000000000..42403eb19
--- /dev/null
+++ b/climbing-stairs/mrlee7.py
@@ -0,0 +1,8 @@
+class Solution:
+    def climbStairs(self, n: int) -> int:
+        stairs = {1: 1, 2: 2}
+
+        for i in range(3, n + 1):
+            stairs[i] = stairs[i - 1] + stairs[i - 2]
+
+        return stairs[n]
diff --git a/longest-consecutive-sequence/mrlee7.py b/longest-consecutive-sequence/mrlee7.py
new file mode 100644
index 000000000..eeb18ec35
--- /dev/null
+++ b/longest-consecutive-sequence/mrlee7.py
@@ -0,0 +1,36 @@
+from typing import List
+
+"""
+Ideation:
+    배열을 정렬한 뒤, 인접한 숫자들을 비교하면서 가장 긴 연속 수열의 길이를 구한다.
+    
+    - 같은 숫자는 중복이므로 건너뛴다.
+    - 현재 숫자 + 1 이 다음 숫자와 같으면 연속된 수이므로 길이를 증가시킨다.
+    - 연속이 끊기면 최대 길이를 갱신하고 길이를 1로 초기화한다.
+
+Time Complexity: O(n log n)
+Space Complexity: O(1)
+"""
+
+
+class Solution:
+
+    def longestConsecutive(self, nums: List[int]) -> int:
+        if len(nums) == 0:
+            return 0
+
+        longest = 0
+        length = 1
+
+        nums.sort()
+
+        for idx in range(len(nums) - 1):
+            if nums[idx] == nums[idx + 1]:
+                continue
+            if nums[idx] + 1 == nums[idx + 1]:
+                length += 1
+            else:
+                longest = max(longest, length)
+                length = 1
+        longest = max(longest, length)
+        return longest
diff --git a/product-of-array-except-self/mrlee7.py b/product-of-array-except-self/mrlee7.py
new file mode 100644
index 000000000..3b732920a
--- /dev/null
+++ b/product-of-array-except-self/mrlee7.py
@@ -0,0 +1,18 @@
+from typing import List
+
+
+class Solution:
+    def productExceptSelf(self, nums: List[int]) -> List[int]:
+        result = [0] * len(nums)
+
+        prefix_product = 1
+        for index in range(len(nums)):
+            result[index] = prefix_product
+            prefix_product *= nums[index]
+
+        suffix_product = 1
+        for index in range(len(nums) - 1, -1, -1):
+            result[index] *= suffix_product
+            suffix_product *= nums[index]
+
+        return result
diff --git a/top-k-frequent-elements/mrlee7.py b/top-k-frequent-elements/mrlee7.py
new file mode 100644
index 000000000..17c1a8213
--- /dev/null
+++ b/top-k-frequent-elements/mrlee7.py
@@ -0,0 +1,19 @@
+from typing import List
+
+"""
+Ideation
+    해시맵에 각 원소별 빈도수를 저장한 뒤, 빈도수 높은 순으로 정렬한 다음 앞에서 k개를 반환합니다.
+Time Complexity: O(n)
+Space Complexity: O(n + m log m)
+"""
+
+class Solution:
+    def topKFrequent(self, nums: List[int], k: int) -> List[int]:
+        frequency = {}
+        for num in nums:
+            frequency[num] = frequency.get(num, 0) + 1
+        sorted_nums = sorted(frequency, key=lambda num: frequency[num], reverse=True)
+
+        return sorted_nums[:k]
+
+
diff --git a/valid-anagram/mrlee7.py b/valid-anagram/mrlee7.py
new file mode 100644
index 000000000..e0738152b
--- /dev/null
+++ b/valid-anagram/mrlee7.py
@@ -0,0 +1,11 @@
+class Solution:
+    """
+    Ideation:
+        애너그램은 문자열 내 배치만 다를 뿐, 동일한 문자들이 동일한 카운트로 보장되어야 한다.
+        이를 위해 문자 기준으로 정렬하고 같은지 확인합니다.
+    Time Complexity: O(n log n)
+    Space Complexity: O(1)
+    """
+
+    def isAnagram(self, s: str, t: str) -> bool:
+        return sorted(s) == sorted(t)