Create minimum-score-of-a-path-between-two-cities.cpp

Author: kamyu104

C++/minimum-score-of-a-path-between-two-cities.cpp

@@ -0,0 +1,42 @@
+// Time:  O(n + m), m = len(roads)
+// Space: O(n + m)
+
+// bfs
+class Solution {
+public:
+    int minScore(int n, vector<vector<int>>& roads) {
+        vector<vector<pair<int, int>>> adj(n);
+        for (const auto& r : roads) {
+            adj[r[0] - 1].emplace_back(r[1] - 1, r[2]);
+            adj[r[1] - 1].emplace_back(r[0] - 1, r[2]);
+        }
+        const auto& bfs = [&]() {
+            vector<bool> lookup(size(adj));
+            vector<int> q = {0};
+            lookup[0] = true;
+            while (!empty(q)) {
+                vector<int> new_q;
+                for (const auto& u : q) {
+                    for (const auto& [v, w] : adj[u]) {
+                        if (lookup[v]) {
+                            continue;
+                        }
+                        lookup[v] = true;
+                        new_q.emplace_back(v);
+                    }
+                }
+                q = move(new_q);
+            }
+            return lookup;
+        };
+
+        const auto& lookup = bfs();
+        int result = numeric_limits<int>::max();
+        for (const auto& r : roads) {
+            if (lookup[r[0] - 1]) {
+                result = min(result, r[2]);
+            }
+        }
+        return result;
+    }
+};