May 16

Author: siddydutta

2025-05-May-LeetCoding-Challenge/Longest Unequal Adjacent Groups Subsequence II.py

@@ -0,0 +1,50 @@
+class Solution:
+    def __is_eligible(self, str1: str, str2: str) -> bool:
+        if len(str1) != len(str2):
+            return False
+        flag = False
+        for ch1, ch2 in zip(str1, str2):
+            if ch1 != ch2:
+                if flag is True:
+                    # hamming distance > 1
+                    return False
+                flag = True
+        # hamming distance == 1
+        return flag
+
+    def getWordsInLongestSubsequence(self, words: list[str], groups: list[int]) -> list[str]:
+        n = len(words)
+        dp, parent = [1] * n, [-1] * n
+        max_len = 0
+
+        for i in range(n):
+            for j in range(i):
+                if groups[i] != groups[j] and \
+                    self.__is_eligible(words[i], words[j]) and \
+                        dp[j] + 1 > dp[i]:
+                    dp[i] = dp[j] + 1
+                    parent[i] = j
+            max_len = max(max_len, dp[i])
+
+        result = []
+        for i in range(n):
+            if dp[i] == max_len:
+                while i != -1:
+                    result.append(words[i])
+                    i = parent[i]
+                break
+        return list(reversed(result))
+
+
+def main():
+    words = ['bab', 'dab', 'cab']
+    groups = [1, 2, 2]
+    assert Solution().getWordsInLongestSubsequence(words, groups) == ['bab', 'dab']
+
+    words = ['a', 'b', 'c', 'd']
+    groups = [1, 2, 3, 4]
+    assert Solution().getWordsInLongestSubsequence(words, groups) == ['a', 'b', 'c', 'd']
+
+
+if __name__ == '__main__':
+    main()

2025-05-May-LeetCoding-Challenge/README.md

@@ -19,7 +19,7 @@
 | May 13 | [3335. Total Characters in String After Transformations I](https://leetcode.com/problems/total-characters-in-string-after-transformations-i/) | Medium | Solved |
 | May 14 | [3337. Total Characters in String After Transformations II](https://leetcode.com/problems/total-characters-in-string-after-transformations-ii/) | Hard | Unsolved |
 | May 15 | [2900. Longest Unequal Adjacent Groups Subsequence I](https://leetcode.com/problems/longest-unequal-adjacent-groups-subsequence-i/) | Easy | Solved |
-| May 16 | []() |  |  |
+| May 16 | [2901. Longest Unequal Adjacent Groups Subsequence II](https://leetcode.com/problems/longest-unequal-adjacent-groups-subsequence-ii/) | Medium | Unsolved |
 | May 17 | []() |  |  |
 | May 18 | []() |  |  |
 | May 19 | []() |  |  |
@@ -41,5 +41,5 @@
 | Level  | Problems | Solved | Unsolved |
 | ---    | --- | --- | --- |
 | Easy   | 4 | 4 | 0 |
-| Medium | 7 | 7 | 0 |
+| Medium | 8 | 7 | 1 |
 | Hard   | 3 | 1 | 2 |