hdu2544 spfa 第一弹 如果让我说：我只能说，实力决定一切

#include<iostream>#include<algorithm>#include<stack>#include<cstdio>#include<queue>#include<string.h>#define inf 1<<30using namespace std;int N,M,T;int dis[201];int vis[201];int head[201];queue<int>S;struct Edge{    int to,w,next;}e[20010];void init(){    memset(head,-1,sizeof(head));    memset(vis,0,sizeof(vis));    for(int i=0; i<=N; i++)        dis[i]=inf;    dis[1]=0;}void Build_Tree(int u,int v,int weight){    e[T].to=v;    e[T].w=weight;    e[T].next=head[u];    head[u]=T++;}int spfa(int pox){    int tem;    S.push(pox);    while(!S.empty())    {        tem=S.front();        S.pop();        vis[tem]=0;        for(int i=head[tem]; i!=-1; i=e[i].next)        {            int t=e[i].to;            if(dis[t]>dis[tem]+e[i].w)            {                dis[t]=dis[tem]+e[i].w;                if(!vis[t])                {                    S.push(t);                    vis[t]=1;                }            }        }    }    return dis[N];}int main(){    int Tu,Tv,Tweight;    while(scanf("%d%d",&N,&M),N+M)    {        T=0;        init();        for(int i=0; i<M; i++)        {            scanf("%d%d%d",&Tu,&Tv,&Tweight);            Build_Tree(Tu,Tv,Tweight);            Build_Tree(Tv,Tu,Tweight);        }        printf("%d\n",spfa(1));    }    return 0;}