UVALive - 5854 最短路

求出加油站两两之间的最短路，判断下即可

#include<iostream>
#include<cstring>
#include <cstdio>
#include<string>
#include<queue>
#include<vector> 
#include<map>
#include <set>
#include<ctime>
#include<cmath>
#include <cstdlib>
#include<algorithm>
#include <iomanip>
using namespace std;

const int N = 10000;
const int INF = ((1<<30)-1);
int oil[N];
char str1[100],str2[100];


int dis[N],q[N],n;
bool vis[N];
void spfa(int s,vector< pair<int,int> > list[N]){
    for(int i=0;i<N;i++) dis[i]=INF;
    memset(vis,0,sizeof(vis));
    int head=0,tail=0;
    q[tail++]=s; dis[s]=0,vis[s]=true; 
    while(head!=tail){
        int u=q[head];
        for(int i=0;i<list[u].size();i++){
            int v=list[u][i].first,w=list[u][i].second;
            if(dis[v]>dis[u]+w){
                dis[v]=dis[u]+w;
                if(!vis[v]){
                    vis[v]=true; 
                    q[tail++]=v;
                    if(tail==N-10) tail=0;
                }
            }
        }
        vis[u]=false; head++;
        if(head==N-10) head=0;
    }
}

vector< pair<int,int> > G[N],g[N];

int main(){
    int n,m,k;
    while(scanf("%d%d%d",&n,&m,&k)!=EOF){
        k=k*10;
        for(int i=0;i<=2*n;i++) G[i].clear();
        for(int i=0;i<=2*n;i++) g[i].clear();
        if(!n&&!m&&!k) return 0;
        map<string,int> mpp;
        int src=1,des=2,cnt=3;
        scanf("%s%s",str1,str2);
        mpp[str1]=src; mpp[str2]=des;
        for(int i=0;i<n;i++){
            int u,v,w;
            scanf("%s%s%d",str1,str2,&w);
            if(w>k) continue;
            if(!mpp[str1]) mpp[str1]=cnt++;
            if(!mpp[str2]) mpp[str2]=cnt++;
            u=mpp[str1],v=mpp[str2];
            G[u].push_back(make_pair(v,w));
            G[v].push_back(make_pair(u,w));
        }
        int tail=0;
        for(int i=0;i<m;i++){
            scanf("%s",str1);
            oil[tail++]=mpp[str1];
        }
        oil[tail++]=src; oil[tail++]=des;
        for(int i=0;i<tail;i++){
            int u=oil[i];
            spfa(u,G);
            for(int j=0;j<i;j++){
                int v=oil[j];
                if(dis[v]>k) {
                    g[u].push_back(make_pair(v,INF));
                    g[v].push_back(make_pair(u,INF));
                }
                else{
                    g[u].push_back(make_pair(v,dis[v]));
                    g[v].push_back(make_pair(u,dis[v]));
                }
            }
        }
        spfa(src,g);
        int ans=dis[des];
        if(ans>=INF||ans==-1) printf("-1\n");
        else printf("%d\n",ans);
    }
}