adding algo

Author: ivanpenaloza

src/my_project/interviews/top_150_questions_round_22/ex_23_find_index_first_occurence.py

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+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 needle == haystack[i:i+len_needle]:
+                return i
+            
+        return -1

src/my_project/interviews/top_150_questions_round_22/ex_24_text_justification.py

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+from typing import List, Union, Collection, Mapping, Optional
+from abc import ABC, abstractmethod
+
+class Solution:
+    def fullJustify(self, words: List[str], maxWidth: int) -> List[str]:
+        """
+        Performs text justification by distributing words and spaces across lines of fixed width.
+        
+        Strategy: Build lines word by word until adding the next word would exceed maxWidth.
+        When a line is full, distribute extra spaces evenly using round-robin.
+        """
+        result = []           # Final list of justified lines
+        current_list = []     # Words being accumulated for the current line
+        num_of_letters = 0    # Total character count (excluding spaces) in current_list
+        
+        for word in words:
+            # Check if adding this word exceeds the line width
+            # Formula: letters + new_word_length + minimum_spaces_needed
+            # Minimum spaces = one space between each word = len(current_list)
+            if num_of_letters + len(word) + len(current_list) > maxWidth:
+                # Justify and add the current line to results
+                
+                # Calculate number of gaps between words (n words = n-1 gaps)
+                # Use max(1, ...) to handle single-word lines and avoid division by zero
+                num_gaps = max(1, len(current_list) - 1)
+                
+                # Distribute extra spaces using round-robin
+                # Total spaces needed = maxWidth - num_of_letters
+                extra_spaces = maxWidth - num_of_letters
+                for i in range(extra_spaces):
+                    # Use modulo to cycle through gaps repeatedly
+                    # This ensures spaces are distributed as evenly as possible
+                    gap_index = i % num_gaps
+                    current_list[gap_index] += ' '
+                
+                # Join words into a single justified line and add to result
+                result.append("".join(current_list))
+                
+                # Reset for next line
+                current_list = []
+                num_of_letters = 0
+            
+            # Add current word to the line being built
+            current_list.append(word)
+            num_of_letters += len(word)
+        
+        # form last line by join with space and left justify to maxWidth using ljust (python method)
+        # that means pad additional spaces to the right to make string length equal to maxWidth
+        result.append(" ".join(current_list).ljust(maxWidth))
+        
+        return result

tests/test_150_questions_round_22/test_23_find_index_first_occurence_round_22.py

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+import unittest
+from src.my_project.interviews.top_150_questions_round_22\
+.ex_23_find_index_first_occurence import Solution
+
+class FirstOccurrenceIndexTestCase(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)

tests/test_150_questions_round_22/test_24_text_justification_round_22.py

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+import unittest
+from src.my_project.interviews.top_150_questions_round_22\
+.ex_24_text_justification import Solution
+
+class TextJustificationTestCase(unittest.TestCase):
+
+    def test_first_pattern(self):
+        solution = Solution()
+        output = solution.fullJustify(words = ["This", "is", "an", "example", "of", "text", "justification."], maxWidth = 16)
+        target = [
+   "This    is    an",
+   "example  of text",
+   "justification.  "
+]
+
+        self.assertEqual(output, target)
+
+    def test_second_pattern(self):
+        solution = Solution()
+        output = solution.fullJustify(words = ["What","must","be","acknowledgment","shall","be"], maxWidth = 16)
+        target = [
+  "What   must   be",
+  "acknowledgment  ",
+  "shall be        "
+]
+        self.assertEqual(output, target)