Create maximum-score-of-a-node-sequence.cpp

Author: kamyu104

C++/maximum-score-of-a-node-sequence.cpp

@@ -0,0 +1,38 @@
+// Time:  O(|V| + |E|)
+// Space: O(|V|)
+
+// graph
+class Solution {
+public:
+    int maximumScore(vector<int>& scores, vector<vector<int>>& edges) {
+        using PII = pair<int, int>;
+        using Heap = vector<PII>;
+        const auto& find_top3 = [&scores](const auto& x, Heap *top3) {            
+            top3->emplace_back(scores[x], x); push_heap(begin(*top3), end(*top3), greater<PII>());
+            if (size(*top3) > 3) {
+                pop_heap(begin(*top3), end(*top3), greater<PII>()); top3->pop_back();
+            }
+        };
+        vector<Heap> top3(size(scores));
+        for (const auto& e : edges) {
+            find_top3(e[1], &top3[e[0]]);
+            find_top3(e[0], &top3[e[1]]);
+        }
+        int result = -1;
+        for (const auto& e : edges) {
+            const int a = e[0], b = e[1];
+            for (const auto& [_, c] : top3[a]) {
+                if (c == b) {
+                    continue;
+                }
+                for (const auto& [_, d] : top3[b]) {
+                    if (d == a || d == c) {
+                        continue;
+                    }
+                    result = max(result, scores[a] + scores[b] + scores[c] + scores[d]);
+                }
+            }
+        }
+        return result;
+    }
+};