From 71df1cf6af82ebdcd371bb25fa8a54b58c8ca2a1 Mon Sep 17 00:00:00 2001
From: jonghun <jonghuncu@gmail.com>
Date: Wed, 23 Jul 2025 08:17:08 +0900
Subject: [PATCH 1/6] add rivkode 1-3 questions

---
 contains-duplicate/rivkode.py      | 11 ++++++----
 top-k-frequent-elements/rivkode.py | 35 ++++++++++++++++++++++--------
 two-sum/rivkode.py                 | 18 +++++++++++++++
 3 files changed, 51 insertions(+), 13 deletions(-)
 create mode 100644 two-sum/rivkode.py

diff --git a/contains-duplicate/rivkode.py b/contains-duplicate/rivkode.py
index ecd4489fc..bad1bba98 100644
--- a/contains-duplicate/rivkode.py
+++ b/contains-duplicate/rivkode.py
@@ -5,11 +5,14 @@
 # The size of the set for storing deduplicated elements is proportional to the length of the input list.
 
 class Solution:
-    def containsDuplicate(self, nums: list[int]) -> bool:
-        list_len = len(nums)
-        set_len = len(set(nums))
+    def containsDuplicate(self, nums):
+        list_num = len(nums)
+        set_num = len(set(nums))
 
-        return list_len != set_len
+        if list_num != set_num:
+            return True
+        else:
+            return False
 
 if __name__ == "__main__":
     solution = Solution()
diff --git a/top-k-frequent-elements/rivkode.py b/top-k-frequent-elements/rivkode.py
index d2b585fed..bca5afb1e 100644
--- a/top-k-frequent-elements/rivkode.py
+++ b/top-k-frequent-elements/rivkode.py
@@ -8,18 +8,35 @@
 # - and when sorting takes O(n), hash[x] occupy O(1)
 
 class Solution:
-    def topKFrequent(self, nums: List[int], k: int) -> List[int]:
-        hash = dict()
+    def topKFrequent(self, nums, k):
+        """
+        :type nums: List[int]
+        :type k: int
+        :rtype: List[int]
+        """
 
-        # for loop nums to set count for each element in hash(dictionary)
-        for num in nums:
-            if num in hash:
-                hash[num] += 1
+        dic = {}
+
+        for v in nums:
+            if v in dic:
+                cur = dic[v]
+                cur += 1
+                dic[v] = cur
             else:
-                hash[num] = 1
+                dic[v] = 1
+
+        reverse_desc = sorted(dic.items(), key=lambda item: item[1], reverse=True)
 
-        # sort (TimSort), using lambda function to set a sorting key which is a count
-        return sorted(hash, key=lambda x: hash[x], reverse=True)[:k]
+        n = 0
+        result = []
+        for v in reverse_desc:
+            if n == k:
+                break
+            
+            result.append(v[0])
+            n += 1
+        
+        return result
 
 if __name__ == "__main__":
     solution = Solution()
diff --git a/two-sum/rivkode.py b/two-sum/rivkode.py
new file mode 100644
index 000000000..e9bae5b16
--- /dev/null
+++ b/two-sum/rivkode.py
@@ -0,0 +1,18 @@
+class Solution(object):
+    def twoSum(self, nums, target):
+
+        """
+        :type nums: List[int]
+        :type target: int
+        :rtype: List[int]
+        """
+
+        dic = {}
+        
+        for i, v in enumerate(nums):
+            complement = target - v
+
+            if complement in dic:
+                return [i, dic[complement]]
+            
+            dic[v] = i
\ No newline at end of file

From 8ea479876899b0b67f849a076a2e9134d867e7b6 Mon Sep 17 00:00:00 2001
From: jonghun <jonghuncu@gmail.com>
Date: Sat, 26 Jul 2025 14:53:55 +0900
Subject: [PATCH 2/6] add 4, 5 questions

---
 house-robber/rivkode.py                 | 18 ++++++++++++++++++
 longest-consecutive-sequence/rivkode.py | 19 +++++++++++++++++++
 two-sum/rivkode.py                      |  2 +-
 3 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 house-robber/rivkode.py
 create mode 100644 longest-consecutive-sequence/rivkode.py

diff --git a/house-robber/rivkode.py b/house-robber/rivkode.py
new file mode 100644
index 000000000..98136d628
--- /dev/null
+++ b/house-robber/rivkode.py
@@ -0,0 +1,18 @@
+class Solution(object):
+    def rob(self, nums):
+        """
+        :type nums: List[int]
+        :rtype: int
+        """
+        memo = {}
+
+        def dfs(start):
+            if start in memo:
+                return memo[start]
+            if not start < len(nums):
+                memo[start] = 0
+            else:
+                memo[start] = max(nums[start] + dfs(start + 2), dfs(start + 1))
+            return memo[start]
+
+        return dfs(0)
diff --git a/longest-consecutive-sequence/rivkode.py b/longest-consecutive-sequence/rivkode.py
new file mode 100644
index 000000000..81427d1ac
--- /dev/null
+++ b/longest-consecutive-sequence/rivkode.py
@@ -0,0 +1,19 @@
+class Solution(object):
+    def longestConsecutive(self, nums):
+        """
+        :type nums: List[int]
+        :rtype: int
+        """
+        num_set = set(nums)
+        longest = 0
+
+        for num in nums:
+            if num - 1 in num_set:
+                continue
+            
+            length = 1
+            while num + length in num_set:
+                length += 1
+            longest = max(length, longest)
+        return longest
+        
\ No newline at end of file
diff --git a/two-sum/rivkode.py b/two-sum/rivkode.py
index e9bae5b16..b12ccb420 100644
--- a/two-sum/rivkode.py
+++ b/two-sum/rivkode.py
@@ -15,4 +15,4 @@ def twoSum(self, nums, target):
             if complement in dic:
                 return [i, dic[complement]]
             
-            dic[v] = i
\ No newline at end of file
+            dic[v] = i

From 9004ccde6385cc7dd08cd35552f901c4e9cc6ca9 Mon Sep 17 00:00:00 2001
From: jonghun <jonghuncu@gmail.com>
Date: Sat, 26 Jul 2025 15:05:26 +0900
Subject: [PATCH 3/6] fix 3 questions to use get(v,0)

---
 top-k-frequent-elements/rivkode.py | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/top-k-frequent-elements/rivkode.py b/top-k-frequent-elements/rivkode.py
index bca5afb1e..a8c34aa82 100644
--- a/top-k-frequent-elements/rivkode.py
+++ b/top-k-frequent-elements/rivkode.py
@@ -18,12 +18,7 @@ def topKFrequent(self, nums, k):
         dic = {}
 
         for v in nums:
-            if v in dic:
-                cur = dic[v]
-                cur += 1
-                dic[v] = cur
-            else:
-                dic[v] = 1
+            dic[v] = dic.get(v, 0) + 1
 
         reverse_desc = sorted(dic.items(), key=lambda item: item[1], reverse=True)
 

From 3225a05c5f7323ca7dade086bf9858ef070b2e2c Mon Sep 17 00:00:00 2001
From: jonghun <jonghuncu@gmail.com>
Date: Sat, 26 Jul 2025 15:22:51 +0900
Subject: [PATCH 4/6] add empty line

---
 two-sum/rivkode.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/two-sum/rivkode.py b/two-sum/rivkode.py
index b12ccb420..b916e4986 100644
--- a/two-sum/rivkode.py
+++ b/two-sum/rivkode.py
@@ -16,3 +16,4 @@ def twoSum(self, nums, target):
                 return [i, dic[complement]]
             
             dic[v] = i
+

From bba96426783cf9691940d3cf0992ed92c04dfc54 Mon Sep 17 00:00:00 2001
From: jonghun <jonghuncu@gmail.com>
Date: Sat, 26 Jul 2025 15:23:57 +0900
Subject: [PATCH 5/6] add empty line

---
 contains-duplicate/rivkode.py           | 3 +++
 house-robber/rivkode.py                 | 3 +++
 longest-consecutive-sequence/rivkode.py | 3 +++
 top-k-frequent-elements/rivkode.py      | 4 ++++
 two-sum/rivkode.py                      | 4 ++++
 5 files changed, 17 insertions(+)

diff --git a/contains-duplicate/rivkode.py b/contains-duplicate/rivkode.py
index bad1bba98..ab1076354 100644
--- a/contains-duplicate/rivkode.py
+++ b/contains-duplicate/rivkode.py
@@ -28,3 +28,6 @@ def containsDuplicate(self, nums):
         print(f"start {index} test")
         print(f"input : {test}")
         print(f"Is valid palindrome ? {solution.containsDuplicate(test)}\n")
+
+
+
diff --git a/house-robber/rivkode.py b/house-robber/rivkode.py
index 98136d628..66ae761d2 100644
--- a/house-robber/rivkode.py
+++ b/house-robber/rivkode.py
@@ -16,3 +16,6 @@ def dfs(start):
             return memo[start]
 
         return dfs(0)
+
+
+
diff --git a/longest-consecutive-sequence/rivkode.py b/longest-consecutive-sequence/rivkode.py
index 81427d1ac..6d54ca641 100644
--- a/longest-consecutive-sequence/rivkode.py
+++ b/longest-consecutive-sequence/rivkode.py
@@ -16,4 +16,7 @@ def longestConsecutive(self, nums):
                 length += 1
             longest = max(length, longest)
         return longest
+        
+
+
         
\ No newline at end of file
diff --git a/top-k-frequent-elements/rivkode.py b/top-k-frequent-elements/rivkode.py
index a8c34aa82..e1989d7d1 100644
--- a/top-k-frequent-elements/rivkode.py
+++ b/top-k-frequent-elements/rivkode.py
@@ -50,3 +50,7 @@ def topKFrequent(self, nums, k):
         print(f"start{i}")
         print(f"input : {nums}, {k}")
         print(f"result : {result}")
+
+
+
+
diff --git a/two-sum/rivkode.py b/two-sum/rivkode.py
index b916e4986..8e4a84b79 100644
--- a/two-sum/rivkode.py
+++ b/two-sum/rivkode.py
@@ -17,3 +17,7 @@ def twoSum(self, nums, target):
             
             dic[v] = i
 
+
+
+
+

From 3c24c20fa47ba9c87df689fabc4ae38b0235f06e Mon Sep 17 00:00:00 2001
From: jonghun <jonghuncu@gmail.com>
Date: Sat, 26 Jul 2025 15:30:06 +0900
Subject: [PATCH 6/6] add empty

---
 longest-consecutive-sequence/rivkode.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/longest-consecutive-sequence/rivkode.py b/longest-consecutive-sequence/rivkode.py
index 6d54ca641..88cdb89fb 100644
--- a/longest-consecutive-sequence/rivkode.py
+++ b/longest-consecutive-sequence/rivkode.py
@@ -19,4 +19,4 @@ def longestConsecutive(self, nums):
         
 
 
-        
\ No newline at end of file
+