Jan 27

Author: siddydutta

2025-01-January-LeetCoding-Challenge/Course Schedule IV.py

@@ -0,0 +1,38 @@
+from itertools import product
+from typing import List
+
+
+class Solution:
+    def checkIfPrerequisite(
+        self, numCourses: int, prerequisites: List[List[int]], queries: List[List[int]]
+    ) -> List[bool]:
+        is_prerequisite = [[False] * numCourses for _ in range(numCourses)]
+        for u, v in prerequisites:
+            is_prerequisite[u][v] = True
+
+        for inter in range(numCourses):
+            for u, v in product(range(numCourses), range(numCourses)):
+                is_prerequisite[u][v] |= is_prerequisite[u][inter] and is_prerequisite[inter][v]
+
+        return [is_prerequisite[u][v] for u, v in queries]
+
+
+def main():
+    numCourses = 2
+    prerequisites = [[1, 0]]
+    queries = [[0, 1], [1, 0]]
+    assert Solution().checkIfPrerequisite(numCourses, prerequisites, queries) == [False, True]
+
+    numCourses = 2
+    prerequisites = []
+    queries = [[1, 0], [0, 1]]
+    assert Solution().checkIfPrerequisite(numCourses, prerequisites, queries) == [False, False]
+
+    numCourses = 3
+    prerequisites = [[1, 2], [1, 0], [2, 0]]
+    queries = [[1, 0], [1, 2]]
+    assert Solution().checkIfPrerequisite(numCourses, prerequisites, queries) == [True, True]
+
+
+if __name__ == '__main__':
+    main()

2025-01-January-LeetCoding-Challenge/README.md

@@ -28,8 +28,8 @@
 | January 23 | [1267. Count Servers that Communicate](https://leetcode.com/problems/count-servers-that-communicate/) | Medium | Solved |
 | January 24 | [802. Find Eventual Safe States](https://leetcode.com/problems/find-eventual-safe-states/) | Medium | Unsolved |
 | January 25 | [2948. Make Lexicographically Smallest Array by Swapping Elements](https://leetcode.com/problems/make-lexicographically-smallest-array-by-swapping-elements/) | Medium | Solved |
-| January 26 | []() |  |  |
-| January 27 | []() |  |  |
+| January 26 | [2127. Maximum Employees to Be Invited to a Meeting](https://leetcode.com/problems/maximum-employees-to-be-invited-to-a-meeting/) | Hard | Unsolved |
+| January 27 | [1462. Course Schedule IV](https://leetcode.com/problems/course-schedule-iv/) | Medium | Solved |
 | January 28 | []() |  |  |
 | January 29 | []() |  |  |
 | January 30 | []() |  |  |
@@ -40,5 +40,5 @@
 | Level  | Problems | Solved | Unsolved |
 | ---    | --- | --- | --- |
 | Easy   | 4 | 4 | 0 |
-| Medium | 18 | 15 | 3 |
-| Hard   | 2 | 0 | 2 |
+| Medium | 19 | 16 | 3 |
+| Hard   | 3 | 0 | 3 |