prim算法加堆优化

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <queue>
using namespace std;
typedef long long LL;
typedef pair<int, int>P;
const int INF = 11111111;
int a[105][105];//邻接矩阵
int vis[105] = {0}, dis[105];
LL ans = 0;
int n, cnt = 1;//n是顶点个数
void Prim() {//把0当成源点
    priority_queue<P, vector<P>,greater<P> >que;
    fill(vis, vis + n, 0);
    while (!que.empty()) que.pop();
    P q;
    for (int i = 1; i < n; i++) {
        if (a[0][i] != INF)
            que.push(P(a[0][i],i));
    }
    vis[0] = 1;
    while (cnt < n) {//cnt是最小生成树的顶点数
        q = que.top();
        que.pop();
        if (vis[q.second]) continue;
        ans += q.first;
        vis[q.second] = 1;
        cnt++;
        for (int i = 0; i < n; i++) {
            if (!vis[i]) {
                    que.push(P(a[q.second][i],i));
            }
        }
    }
}
int main()
{
    //freopen("in.txt","r",stdin);
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	while (cin >> n) {
        //cin >> n;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                cin >> a[i][j];
            }
        }
        Prim();
        cout << ans << endl;
        ans = 0;
        cnt = 1;
	}
	return 0;
}