diff --git a/contains-duplicate/6kitty.py b/contains-duplicate/6kitty.py
new file mode 100644
index 0000000000..a5a33a9986
--- /dev/null
+++ b/contains-duplicate/6kitty.py
@@ -0,0 +1,20 @@
+#
+# @lc app=leetcode id=217 lang=python3
+#
+# [217] Contains Duplicate
+#
+
+# @lc code=start
+class Solution:
+    def containsDuplicate(self, nums: List[int]) -> bool:
+        # list로 하니까 시간 초과 떠서 set으로 변경
+        idx=set()
+        for i in nums:
+            if i in idx:
+                return True
+            idx.add(i)
+        # null 방지 
+        return False
+        
+# @lc code=end
+
diff --git a/house-robber/6kitty.py b/house-robber/6kitty.py
new file mode 100644
index 0000000000..8a1b65a470
--- /dev/null
+++ b/house-robber/6kitty.py
@@ -0,0 +1,17 @@
+#
+# @lc app=leetcode id=198 lang=python3
+#
+# [198] House Robber
+#
+
+# @lc code=start
+class Solution:
+    def rob(self, nums: List[int]) -> int:
+        pre=0
+        cur=0
+        for num in nums:
+            pre, cur = cur, max(num + pre, cur)
+        return cur
+        
+# @lc code=end
+
diff --git a/longest-consecutive-sequence/6kitty.py b/longest-consecutive-sequence/6kitty.py
new file mode 100644
index 0000000000..249cfbf91d
--- /dev/null
+++ b/longest-consecutive-sequence/6kitty.py
@@ -0,0 +1,28 @@
+#
+# @lc app=leetcode id=128 lang=python3
+#
+# [128] Longest Consecutive Sequence
+#
+from typing import List
+# @lc code=start
+class Solution:
+    def longestConsecutive(self, nums: List[int]) -> int:
+        nums.sort()
+        long=0
+
+        leng=1
+        for i in range(len(nums)-1):
+            if nums[i]==nums[i+1]:
+                continue
+            if nums[i]+1==nums[i+1]:
+                leng+=1
+            else:
+                long=max(long,leng)
+                leng=1
+        # 아래를 추가해야 for문 다 돌았을 때 leng이 최고인 경우 반영
+        long=max(long,leng)
+        return long
+        
+        
+# @lc code=end
+
diff --git a/top-k-frequent-elements/6kitty.py b/top-k-frequent-elements/6kitty.py
new file mode 100644
index 0000000000..5d9c94f5a2
--- /dev/null
+++ b/top-k-frequent-elements/6kitty.py
@@ -0,0 +1,25 @@
+#
+# @lc app=leetcode id=347 lang=python3
+#
+# [347] Top K Frequent Elements
+#
+
+# @lc code=start
+class Solution:
+    def topKFrequent(self, nums: List[int], k: int) -> List[int]:
+        sol = {}
+        for i in nums:
+            sol[i] = sol.get(i, 0) + 1
+        
+        sorted_items = sorted(sol.items(), key=lambda x: x[1], reverse=True)
+        
+        ssol = []
+        for i in range(k):
+            ssol.append(sorted_items[i][0])
+        
+        return ssol
+
+
+        
+# @lc code=end
+
diff --git a/two-sum/6kitty.py b/two-sum/6kitty.py
new file mode 100644
index 0000000000..0e3012ea16
--- /dev/null
+++ b/two-sum/6kitty.py
@@ -0,0 +1,16 @@
+#
+# @lc app=leetcode id=1 lang=python3
+#
+# [1] Two Sum
+#
+
+# @lc code=start
+class Solution:
+    def twoSum(self, nums: List[int], target: int) -> List[int]:
+        for i,num in enumerate(nums):
+            for j in range(i+1,len(nums)):
+                if num + nums[j] == target:
+                    return [i,j]
+        
+# @lc code=end
+