'commit'

TangDou/AcWing_TiGao/T3/MinialSpanningTree/1143.cpp

@@ -0,0 +1,48 @@
+#include <bits/stdc++.h>
+using namespace std;
+const int N = 2010, M = 10010;
+int n, m, p[N];
+
+struct Edge {
+    int a, b, c;
+    bool operator<(const Edge &t) const {
+        return c < t.c;
+    }
+} edge[M];
+int el;
+
+int find(int x) {
+    if (p[x] != x) p[x] = find(p[x]);
+    return p[x];
+}
+
+int res;
+
+int main() {
+    cin >> n >> m;
+
+    // 初始化并查集
+    for (int i = 1; i <= n; i++) p[i] = i;
+
+    for (int i = 0; i < m; i++) {
+        int a, b, c, t;
+        cin >> t >> a >> b >> c;
+        if (t == 1) // 必选的加入到同一个并查集
+            p[find(a)] = find(b), res += c;
+        else
+            // 记录可选边有哪些
+            edge[el++] = {a, b, c};
+    }
+    // 对可选边进行由小到大排序
+    sort(edge, edge + el);
+
+    // 枚举每条可选边
+    for (int i = 0; i < el; i++) {
+        int a = find(edge[i].a), b = find(edge[i].b), c = edge[i].c;
+        if (a != b) p[a] = b, res += c;
+    }
+
+    // 输出最短长度
+    cout << res << endl;
+    return 0;
+}