diff --git a/contains-duplicate/do-heewan.py b/contains-duplicate/do-heewan.py
new file mode 100644
index 000000000..59c26ce8b
--- /dev/null
+++ b/contains-duplicate/do-heewan.py
@@ -0,0 +1,8 @@
+class Solution:
+    def containsDuplicate(self, nums: List[int]) -> bool:
+        sets = set(nums)
+
+        if len(nums) != len(sets):
+            return True
+        return False
+
diff --git a/top-k-frequent-elements/do-heewan.py b/top-k-frequent-elements/do-heewan.py
new file mode 100644
index 000000000..d17102515
--- /dev/null
+++ b/top-k-frequent-elements/do-heewan.py
@@ -0,0 +1,15 @@
+class Solution(object):
+    def topKFrequent(self, nums, k):
+        count = {}
+        result = []
+
+        for i in nums:
+            if i not in count:
+                count[i] = 1
+            else:
+                count[i] += 1
+
+        count = sorted(count.items(), key=lambda x : x[1], reverse=True)
+        
+        return [item[0] for item in count[:k]]
+
diff --git a/two-sum/do-heewan.py b/two-sum/do-heewan.py
new file mode 100644
index 000000000..5fdaeee44
--- /dev/null
+++ b/two-sum/do-heewan.py
@@ -0,0 +1,10 @@
+class Solution(object):
+    def twoSum(self, nums, target):
+        result = []
+        for i in range(len(nums)-1):
+            for j in range(i+1, len(nums)):
+                if (nums[i] + nums[j] == target):
+                    result.append(i)
+                    result.append(j)
+                    
+        return result