diff --git a/src/my_project/interviews/amazon_high_frequency_23/round_2/two_sum_round_3.py b/src/my_project/interviews/amazon_high_frequency_23/round_2/two_sum_round_3.py
new file mode 100644
index 00000000..534c7ec3
--- /dev/null
+++ b/src/my_project/interviews/amazon_high_frequency_23/round_2/two_sum_round_3.py
@@ -0,0 +1,16 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+
+class Solution:
+    def twoSum(self, nums: List[int], target: int) -> List[int]:
+
+        answer = dict()
+
+        for k, v in enumerate(nums):
+
+            if v in answer:
+                return [answer[v], k]
+            else:
+                answer[target - v] = k
+        
+        return []
\ No newline at end of file
diff --git a/src/my_project/interviews/amazon_high_frequency_23/round_2/valid_palindrome_round_3.py b/src/my_project/interviews/amazon_high_frequency_23/round_2/valid_palindrome_round_3.py
new file mode 100644
index 00000000..eaab0a37
--- /dev/null
+++ b/src/my_project/interviews/amazon_high_frequency_23/round_2/valid_palindrome_round_3.py
@@ -0,0 +1,23 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+import re
+
+class Solution:
+    def isPalindrome(self, s: str) -> bool:
+
+        # To lowercase
+        s = s.lower()
+
+        # Remove non-alphanumeric characters
+        s = re.sub(pattern='[^a-zA-Z0-9]', repl='', string=s)
+
+        # Determine if it is palindrome or not 
+
+        len_s = len(s)
+
+        for i in range(len_s//2):
+
+            if s[i] != s[len_s - 1 -i]:
+                return False 
+            
+        return True 
\ No newline at end of file
diff --git a/src/my_project/interviews/top_150_questions_round_21/ransom_note.py b/src/my_project/interviews/top_150_questions_round_21/ransom_note.py
new file mode 100644
index 00000000..adb3bb13
--- /dev/null
+++ b/src/my_project/interviews/top_150_questions_round_21/ransom_note.py
@@ -0,0 +1,11 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+
+class Solution:
+    def canConstruct(self,ransomNote: str, magazine: str) -> bool:
+
+        for c in set(ransomNote):
+            if ransomNote.count(c) > magazine.count(c):
+                return False 
+            
+        return True 
\ No newline at end of file
diff --git a/tests/test_150_questions_round_21/test_ransom_note_round_21.py b/tests/test_150_questions_round_21/test_ransom_note_round_21.py
new file mode 100644
index 00000000..4e0c2b59
--- /dev/null
+++ b/tests/test_150_questions_round_21/test_ransom_note_round_21.py
@@ -0,0 +1,15 @@
+import unittest
+from src.my_project.interviews.top_150_questions_round_21\
+.ransom_note import Solution
+
+class RansomeNoteTestCase(unittest.TestCase):
+
+    def test_is_ransome_note(self):
+        solution = Solution()
+        output = solution.canConstruct(ransomNote="aa", magazine="aab")
+        self.assertTrue(output)
+
+    def test_is_no_ransome_note(self):
+        solution = Solution()
+        output = solution.canConstruct(ransomNote="a", magazine="b")
+        self.assertFalse(output)
\ No newline at end of file