adding algo

Author: ivanpenaloza

src/my_project/interviews/amazon_high_frequency_23/round_2/valid_palindrome_4.py

@@ -0,0 +1,21 @@
+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 

src/my_project/interviews/top_150_questions_round_21/find_index_first_occurrence.py

@@ -0,0 +1,14 @@
+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+
+class Solution:
+    def strStr(self, haystack: str, needle: str) -> int:
+
+        len_needle = len(needle)
+        len_haystack = len(haystack)
+
+        for i in range(len_haystack - len_needle + 1):
+            if haystack[i:i+len_needle] == needle:
+                return i 
+            
+        return -1

tests/test_150_questions_round_21/test_find_index_first_occurrence_round_21.py

@@ -0,0 +1,17 @@
+import unittest
+from src.my_project.interviews.top_150_questions_round_21\
+.find_index_first_occurrence import Solution
+
+class FirstOccurrenceIndex(unittest.TestCase):
+
+    def test_first_occurrence_index(self):
+        solution = Solution()
+        output = solution.strStr(haystack="sadbutsad", needle="sad")
+        target = 0 
+        self.assertEqual(output, target)
+
+    def test_no_first_occurrence_index(self):
+        solution = Solution()
+        output = solution.strStr(haystack="leetcode", needle="leeto")
+        target = -1
+        self.assertEqual(output, target)