diff --git a/src/my_project/interviews/amazon_high_frequency_23/common_algos/two_sum_round_20.py b/src/my_project/interviews/amazon_high_frequency_23/common_algos/two_sum_round_20.py
new file mode 100644
index 00000000..6c0c6330
--- /dev/null
+++ b/src/my_project/interviews/amazon_high_frequency_23/common_algos/two_sum_round_20.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/common_algos/valid_palindrome_round_20.py b/src/my_project/interviews/amazon_high_frequency_23/common_algos/valid_palindrome_round_20.py
new file mode 100644
index 00000000..dfc57cd7
--- /dev/null
+++ b/src/my_project/interviews/amazon_high_frequency_23/common_algos/valid_palindrome_round_20.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=r'[^a-zA-Z0-9]', repl='', string=s)
+
+        # Determine if s 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/amazon_high_frequency_23/round_5/design_sql.py b/src/my_project/interviews/amazon_high_frequency_23/round_5/design_sql.py
new file mode 100644
index 00000000..3e929650
--- /dev/null
+++ b/src/my_project/interviews/amazon_high_frequency_23/round_5/design_sql.py
@@ -0,0 +1,111 @@
+from typing import List, Union, Collection, Mapping, Optional, Dict
+
+class Table:
+
+    def __init__(self, name:str, columns: int, rows: Dict, row_count: int = 0):
+        self.name = name 
+        self.columns = columns
+        self.rows = rows 
+        self.row_count = row_count
+
+class SQL:
+
+    def __init__(self, names: List[str], columns: List[int]):
+        """
+        two string arrays, names and columns, both of size n.
+
+        The ith table is represented by the name names[i] and contains columns[i] number of columns
+        """
+        self.names = names 
+        self.columns = columns
+        self.data = {}
+
+        for i in range(0, len(self.names)):
+            self.data[self.names[i]] = Table(
+                name = self.names[i],
+                columns=self.columns[i],
+                rows={}
+            )
+
+        return 
+        
+
+    def ins(self, name: str, row: List[str]) -> bool:
+        """
+        Inserts row into the table name and returns true.
+        If row.length does not match the expected number of columns, or name is not a valid table,
+        returns false without any insertion.
+        """        
+        table: Table = self.data.get(name)
+        if table is None:
+            return False 
+        if len(row) != table.columns:
+            return False 
+        table.row_count += 1
+        table.rows[table.row_count] = row
+
+        return True 
+        
+
+    def rmv(self, name: str, rowId: int) -> None:
+        """
+        Removes the row rowId from the table name.
+        If name is not a valid table or there is no row with id rowId, no removal is performed.
+        """        
+        table: Table = self.data.get(name, None)
+        if table is None:
+            return 
+        
+        if rowId in table.rows:
+            del table.rows[rowId]
+
+        return 
+        
+
+    def sel(self, name: str, rowId: int, columnId: int) -> str:
+        """
+        Returns the value of the cell at the specified rowId and columnId in the table name.
+        If name is not a valid table, or the cell (rowId, columnId) is invalid, returns "<null>".
+        """        
+        null = "<null>"
+        table: Table = self.data.get(name, None)
+        if table is None:
+            return null
+        
+        if rowId not in table.rows:
+            return null
+        
+        try:
+            return table.rows[rowId][columnId - 1]
+        except Exception:
+            return null
+        
+
+    def exp(self, name: str) -> List[str]:
+        """
+        Returns the rows present in the table name.
+        If name is not a valid table, returns an empty array.
+        Each row is represented as a string, with each cell value (including the row's id) separated by a ",".
+        """
+        table: Table = self.data.get(name, None)
+        if table is None:
+            return []
+        
+        result = []
+
+        for row_id, row in table.rows.items():
+            row_str = ",".join(row)
+            result.append(f"{row_id},{row_str}")
+        
+        return result
+
+
+        
+
+
+# Your SQL object will be instantiated and called as such:
+# obj = SQL(names, columns)
+# param_1 = obj.ins(name,row)
+# obj.rmv(name,rowId)
+# param_3 = obj.sel(name,rowId,columnId)
+# param_4 = obj.exp(name)
\ No newline at end of file
diff --git a/src/my_project/interviews/amazon_high_frequency_23/round_5/find_minimum_time_to_finsh_all_jobs_ii.py b/src/my_project/interviews/amazon_high_frequency_23/round_5/find_minimum_time_to_finsh_all_jobs_ii.py
new file mode 100644
index 00000000..cebb1d31
--- /dev/null
+++ b/src/my_project/interviews/amazon_high_frequency_23/round_5/find_minimum_time_to_finsh_all_jobs_ii.py
@@ -0,0 +1,14 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+import math
+
+class Solution:
+    def minimumTime(self, jobs: List[int], workers: List[int]) -> int:
+
+        jobs.sort()
+        workers.sort()
+
+        return max([math.ceil(n/d) for n,d in zip(jobs, workers)])
+
+
+
diff --git a/src/my_project/interviews/top_150_questions_round_22/merge_sorted_array.py b/src/my_project/interviews/top_150_questions_round_22/merge_sorted_array.py
new file mode 100644
index 00000000..aa9bb971
--- /dev/null
+++ b/src/my_project/interviews/top_150_questions_round_22/merge_sorted_array.py
@@ -0,0 +1,13 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+
+class Solution:
+    def merge(self, 
+              nums1: List[int], 
+              m: int, nums2: List[int], 
+              n: int) -> None:
+        
+        nums1[m:m+n] = nums2
+        nums1.sort()
+
+        return nums1
\ No newline at end of file
diff --git a/src/my_project/interviews/top_150_questions_round_22/remove_element.py b/src/my_project/interviews/top_150_questions_round_22/remove_element.py
new file mode 100644
index 00000000..8521e400
--- /dev/null
+++ b/src/my_project/interviews/top_150_questions_round_22/remove_element.py
@@ -0,0 +1,11 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+
+class Solution:
+
+    def removeElement(self, nums: List[int], val: int) -> int:
+
+        while val in nums:
+            nums.remove(val)
+
+        return len(nums)
\ No newline at end of file
diff --git a/tests/test_150_questions_round_22/test_merge_sorted_array_round_22.py b/tests/test_150_questions_round_22/test_merge_sorted_array_round_22.py
new file mode 100644
index 00000000..35ea220c
--- /dev/null
+++ b/tests/test_150_questions_round_22/test_merge_sorted_array_round_22.py
@@ -0,0 +1,12 @@
+import unittest
+from src.my_project.interviews.top_150_questions_round_22\
+.merge_sorted_array import Solution
+
+class MergeSortedArrayTestCase(unittest.TestCase):
+
+    def test_merge_sorted_array(self):
+        solution = Solution()
+        output = solution.merge(nums1=[1,2,3,0,0,0], m=3, nums2=[2,5,6], n=3)
+        target = [1,2,2,3,5,6]
+        for k, v in enumerate(target):
+            self.assertEqual(output[k], v)
\ No newline at end of file
diff --git a/tests/test_150_questions_round_22/test_remove_element_round_22.py b/tests/test_150_questions_round_22/test_remove_element_round_22.py
new file mode 100644
index 00000000..5e5bd4b0
--- /dev/null
+++ b/tests/test_150_questions_round_22/test_remove_element_round_22.py
@@ -0,0 +1,11 @@
+import unittest
+from src.my_project.interviews.top_150_questions_round_22\
+.remove_element import Solution
+
+class RemoveElementTestCase(unittest.TestCase):
+
+    def test_remove_element(self):
+        solution = Solution()
+        output = solution.removeElement(nums=[3,2,2,3], val=3)
+        target = 2
+        self.assertEqual(output, target)
\ No newline at end of file