poj1258(prime水题)

标准最小生成树.

#include<cstdio>
#include<cstring>
using namespace std;
int M[210][210],book[210],dist[210],N;
int Prime(int cur)
{
    int sum=0;
    dist[1]=1;
    memset(book,0,sizeof(book));
    book[cur]=1;
    for(int i=2;i<=N;i++)
    {
        dist[i]=M[cur][i];
    }
    for(int i=1;i<N;i++)
    {
        int index,Min=99999999;
        for(int j=1;j<=N;j++)
        {
            if(!book[j]&&dist[j]<Min)
            {
                Min=dist[j];
                index=j;
            }
        }
        book[index]=1;
        sum+=Min;
        for(int j=1;j<=N;j++)
        {
            if(!book[j]&&dist[j]>M[index][j])
                dist[j]=M[index][j];
        }
    }
    return sum;
}

int main()
{
    while(~scanf("%d",&N))
    {
        for(int i=1;i<=N;i++)
            for(int j=1;j<=N;j++)
            scanf("%d",&M[i][j]);
        printf("%d\n",Prime(1));
    }
    return 0;
}