hdu2544(spfa)

<!-- lang: cpp -->
#include<iostream>
using namespace std;
struct edge
{
    int to;
    double cost;
    edge *next;
    edge(){next=NULL;}
};
struct LNode
{
    int data;
    LNode *next;
    LNode(){next=NULL;}
};
bool list[101];
LNode *h,*e,*p;
edge *graph[101],*tmp;
int n,m,d[101];
void spfa()
{
    int i;
    while(h!=NULL)
    {
        for(tmp=graph[h->data];tmp!=NULL;tmp=tmp->next)
        {
            if(d[tmp->to]>d[h->data]+tmp->cost)
            {
                d[tmp->to]=d[h->data]+tmp->cost;
                if(!list[tmp->to]){
                p->next=new LNode;
                p=p->next;
                p->data=tmp->to;
                list[tmp->to]=1;}
            }
        }
        list[h->data]=0;
        e=h;
        h=h->next;
        delete e;
    }
}
int main()
{
    int i,tmpa,tmpb,tmpc;
    while(cin>>n>>m&&(n!=0||m!=0))
    {
        h=p=NULL;
        for(i=0;i<n;i++)
        {
            d[i]=0xfffffff;
            graph[i]=NULL;
        }
        memset(list,0,sizeof(list));
        d[0]=0;
        h=new LNode;
        h->data=0;
        p=h;
        for(i=0;i<m;i++)
        {
            cin>>tmpa>>tmpb>>tmpc;
            tmp=new edge;
            tmp->to=tmpb-1;
            tmp->cost=tmpc;
            tmp->next=graph[tmpa-1];
            graph[tmpa-1]=tmp;
            tmp=new edge;
            tmp->to=tmpa-1;
            tmp->cost=tmpc;
            tmp->next=graph[tmpb-1];
            graph[tmpb-1]=tmp;
        }
        spfa();
        cout<<d[n-1]<<endl;
    }
    return 0;
}