update

poj/1258.agri-net/main.cc

@@ -0,0 +1,53 @@
+#include <cstdio>
+#include <cstring>
+#include <queue>
+#include <set>
+#include <vector>
+
+using namespace std;
+
+const int N = 100;
+const int INF = 0x3F3F3F3F;
+
+int dist[N];
+
+struct E {
+  int v;
+  int w;
+  E(int v = 0, int w = INF) : v(v), w(w) {}
+  bool operator<(const E &that) const { return this->w > that.w; }
+};
+
+int main() {
+  int n, len, used;
+  while (scanf("%d", &n) != EOF) {
+    vector<vector<E>> adj;
+    for (int i = 0, w; i < n; i++) {
+      adj.push_back(vector<E>());
+      for (int j = 0; j < n; j++) {
+        scanf("%d", &w);
+        adj[i].push_back(E(j, w));
+      }
+    }
+    memset(dist, 0x3F, sizeof(dist));
+    dist[0] = 0, len = 0, used = 1;
+    priority_queue<E> pq;
+    for (int i = 0; i < adj[0].size(); i++) pq.push(adj[0][i]);
+    while (used != n) {
+      E e;
+      do {
+        e = pq.top();
+        pq.pop();
+      } while (dist[e.v] != INF);
+      dist[e.v] = e.w;
+      len += e.w;
+      used++;
+      for (int i = 0; i < adj[e.v].size(); i++) {
+        E &u = adj[e.v][i];
+        if (dist[u.v] == INF) pq.push(u);
+      }
+    }
+    printf("%d\n", len);
+  }
+  return 0;
+}