最小生成树+虚拟源点

链接：链接

思路

• 建立虚拟源点，到每个点的距离

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>

using namespace std;

const int N = 310;

int n;
int w[N][N];
int dist[N];
bool st[N];

int prim()
{
    memset(dist, 0x3f, sizeof dist);
    dist[0] = 0;

    int res = 0;
    for (int i = 0; i < n + 1; i ++ )
    {
        int t = -1;
        for (int j = 0; j <= n; j ++ )
            if (!st[j] && (t == -1 || dist[t] > dist[j]))
                t = j;
        st[t] = true;
        res += dist[t];

        for (int j = 0; j <= n; j ++ ) dist[j] = min(dist[j], w[t][j]);
    }

    return res;
}

int main()
{
    scanf("%d", &n);
    for (int i = 1; i <= n; i ++ )
    {
        scanf("%d", &w[0][i]);
        w[i][0] = w[0][i];
    }

    for (int i = 1; i <= n; i ++ )
        for (int j = 1; j <= n; j ++ )
            scanf("%d", &w[i][j]);

    printf("%d\n", prim());

    return 0;
}