Feb 24

Author: siddydutta

2025-02-February-LeetCoding-Challenge/Most Profitable Path in a Tree.py

@@ -0,0 +1,60 @@
+from collections import defaultdict
+from typing import List
+
+
+class Solution:
+    def mostProfitablePath(self, edges: List[List[int]], bob: int, amount: List[int]) -> int:
+        graph = defaultdict(list)
+        for u, v in edges:
+            graph[u].append(v)
+            graph[v].append(u)
+
+        def dfs_bob(node: int) -> List[int]:
+            if node == 0:
+                return [node]
+            nonlocal visited
+            visited.add(node)
+            path = []
+            for neighbour in graph[node]:
+                if neighbour not in visited:
+                    path = dfs_bob(neighbour)
+                    if path:
+                        return [node] + path
+        visited = set()
+        bob_path = dfs_bob(bob)
+        bob_visited_times = {node: i for i, node in enumerate(bob_path)}
+
+        def dfs_alice(node: int, time: int) -> int:
+            max_amount = float('-inf')
+            nonlocal visited
+            visited.add(node)
+            for neighbour in graph[node]:
+                if neighbour not in visited:
+                    max_amount = max(max_amount, dfs_alice(neighbour, time+1))
+            vertex_income = amount[node]
+            if bob_visited_times.get(node, float('inf')) < time:
+                vertex_income = 0
+            elif bob_visited_times.get(node, float('inf')) == time:
+                vertex_income = amount[node] // 2
+            if max_amount == float('-inf'):
+                return vertex_income
+            return max_amount + vertex_income
+
+        visited = set()
+        return dfs_alice(0, 0)
+
+
+def main():
+    edges = [[0, 1], [1, 2], [1, 3], [3, 4]]
+    bob = 3
+    amount = [-2, 4, 2, -4, 6]
+    assert Solution().mostProfitablePath(edges, bob, amount) == 6
+
+    edges = [[0, 1]]
+    bob = 1
+    amount = [-7280, 2350]
+    assert Solution().mostProfitablePath(edges, bob, amount) == -7280
+
+
+if __name__ == '__main__':
+    main()

2025-02-February-LeetCoding-Challenge/README.md

@@ -27,7 +27,7 @@
 | February 21 | [1261. Find Elements in a Contaminated Binary Tree](https://leetcode.com/problems/find-elements-in-a-contaminated-binary-tree/) | Medium | Solved |
 | February 22 | [1028. Recover a Tree From Preorder Traversal](https://leetcode.com/problems/recover-a-tree-from-preorder-traversal/) | Hard | Solved |
 | February 23 | [889. Construct Binary Tree from Preorder and Postorder Traversal](https://leetcode.com/problems/construct-binary-tree-from-preorder-and-postorder-traversal/) | Medium | Unsolved |
-| February 24 | []() |  |  |
+| February 24 | [2467. Most Profitable Path in a Tree](https://leetcode.com/problems/most-profitable-path-in-a-tree/) | Medium | Unsolved |
 | February 25 | []() |  |  |
 | February 26 | []() |  |  |
 | February 27 | []() |  |  |
@@ -38,5 +38,5 @@
 | Level  | Problems | Solved | Unsolved |
 | ---    | --- | --- | --- |
 | Easy   | 6 | 6 | 0 |
-| Medium | 15 | 12 | 3 |
+| Medium | 16 | 12 | 4 |
 | Hard   | 1 | 1 | 0 |