Hdu 1535 Invitation Cards

Hdu 1535 Invitation Cards

#include
  
   #include
   
    #include#include
    
     using namespace std;const int inf=1<<24;const int N=1000000+5;struct node{    int to,w;    node* next;};node* edge[N];node* reedge[N];int n,m,x,dist[N],inq[N],q[N];void spfa(int flag){    int i,u,h=0,t=1;    node* ptr;    for(i=0; i<=n; i++)    {        dist[i]=inf;        inq[i]=0;    }    dist[1]=0;    inq[1]=1;    q[0]=1;    while(h!=t)    {        u=q[h];        h++;        inq[u]=0;        if(flag==1) ptr=edge[u];        else ptr=reedge[u];        while(ptr)        {            if(dist[ptr->to]>(dist[u]+ptr->w))            {                dist[ptr->to]=dist[u]+ptr->w;                if(inq[ptr->to]==0)                {                    q[t]=ptr->to;                    t++;                    inq[ptr->to]=1;                }            }            ptr=ptr->next;        }    }}int main(){    int cas,i,u,v,w,ans;    scanf("%d",&cas);    while(cas--)    {        scanf("%d%d",&n,&m);        for(i=1; i<=n; i++)        {            edge[i]=NULL;            reedge[i]=NULL;        }        for(i=0; i
     
      to=u;            temp->w=w;            temp->next=NULL;            if(edge[v]==NULL)            {                edge[v]=temp;            }            else            {                temp->next=edge[v];                edge[v]=temp;            }            temp= new node;            temp->to=v;            temp->w=w;            temp->next=NULL;            if(reedge[u]==NULL)            {                reedge[u]=temp;            }            else            {                temp->next=reedge[u];                reedge[u]=temp;            }        }        ans=0;        spfa(1);        for(i=2; i<=n; i++)        {            //printf("%d\n",dist[i]);            ans+=dist[i];        }        spfa(0);        for(i=2; i<=n; i++)        {            ans+=dist[i];        }        printf("%d\n",ans);    }    return 0;}