hdu 4009最小树形图邻接表版

需要注意，因为增加一个零点，最后总点数要加1；

此模板的边和点都从0开始计数

废话一句，厚积方能薄发啊。

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#include<stdio.h>
#include<stdlib.h>
#include<math.h>
#include<string.h>
#define maxn 1005
const int inf =1000000000;
struct Edge
{
    int s,t;
    int cost;
}edge[maxn*maxn];
struct node{
    int x,y,z;
}a[maxn];
int E,nv,ne;
int pre[maxn],Id[maxn],vis[maxn];
int in[maxn];
//最小树形图邻接表版本，三步走，找最小入弧，找有向环，缩环为点
int Directed_MST(int root)//点和边都是从0开始的
{//返回-1 为无最小树形图 返回为最小树形图值
    int i,s,t;
    nv++;
    int  ret = 0;
    while(1)
    {
        //find the smallest in-arc
        for(i=0;i<nv;i++) in[i] = inf,Id[i]=-1,vis[i]=-1;
        for(i = 0;i < ne;i++)
        {
            s = edge[i].s;
            t = edge[i].t;
            if(edge[i].cost>=in[t] || s == t)continue;
            pre[t] = s;
            in[t] = edge[i].cost;
            
        }
        in[root] = 0; pre[root]=root;
        for(i = 0;i < nv;i++)
        {
            ret += in[i];
            if(in[i] == inf)
                return -1;
            //there are some nodes other than root with no in-arc connected to it
        } 
        //find the dir circle
        int Idx = 0;
        for(i = 0;i < nv;i++)if(vis[i]==-1)
        {
            t = i;
            while(vis[t]==-1)
            {
                vis[t] = i;
                t = pre[t];
            }
            if(vis[t]!=i||t==root)continue;
            for(int s = pre[t]; s != t;s = pre[s])
                Id[s] = Idx;
            Id[t] = Idx++;
        }
        if(Idx == 0)  break;//no circle
        for(i = 0;i < nv;i++)  if(Id[i] == -1)
            Id[i] = Idx++;
        //compress the nodes;
        for(i = 0;i < ne;i++)
        {
            int v = edge[i].t;
            edge[i].s = Id[edge[i].s];
            edge[i].t = Id[edge[i].t];
            edge[i].cost -= in[v];
        }
        nv = Idx;
        root = Id[root];
    }
    return ret;
}
void add(int s,int t,int cost)
{
    edge[ne].s=s;
    edge[ne].t=t;
    edge[ne++].cost=cost;
}
int dist(int i,int j)
{
    return abs(a[i].x-a[j].x)+abs(a[i].y-a[j].y)+abs(a[i].z-a[j].z);
}
int main()
{
    int i,j,x,y,z,k,temp;
    while(scanf("%d%d%d%d",&nv,&x,&y,&z)!=EOF)
    {
        ne=0;
        if(nv==0) break;
        for(i=1;i<=nv;i++)
        {
            scanf("%d%d%d",&a[i].x,&a[i].y,&a[i].z);
            add(0,i,a[i].z*x);
        }
        for(i=1;i<=nv;i++)
        {
            scanf("%d",&k);
            for(j=0;j<k;j++)
            {
                scanf("%d",&temp);
                if(temp==i) continue;
                if(a[i].z>=a[temp].z)
                     add(i,temp,dist(i,temp)*y);
                else add(i,temp,dist(i,temp)*y+z);
            }
        }
        printf("%d\n",Directed_MST(0));
    }
    return 0;
}