uva 11377 - Airport Setup

/*
ID:1192432
PROG: castle
LANG: C++
*/
#include <iostream>
#include <string>
#include <map>
#include <vector>
#include <memory.h>
#include <cstdio>
#include <cmath>
#include <queue>
#include <algorithm>
using namespace std;
typedef pair<int,int> pii;

const int MAX=10005,INF=1<<30,w=1;
bool city[2005],
     done[2005];
int n,m,k,Q,l,
    first[2005],next[MAX*2],d[2005],
    u[MAX*2],v[MAX*2];

priority_queue<pii,vector<pii>,greater<pii> > q;

void work(int sta,int end){
    if(sta==end){
        cout<<0<<endl;
        return ;
    }
    int U,dis;
    pii x;

    memset(done,0,sizeof(done));
    for(int i=1;i<=n;i++) d[i]=INF;

    if(city[sta]) dis=0;
    else dis=1;
    d[sta]=dis;
    q.push(make_pair(dis,sta));
    while(!q.empty()){
        x=q.top(); q.pop();

        U=x.second;
        if(done[U])
            continue;
        done[U]=1;
        //cout<<"U: "<<U<<endl;
        for(int e=first[U];e!=-1;e=next[e]){
            if(city[v[e]]) dis=0;
            else dis=1;

            if(d[v[e]]>d[U]+dis){
                d[v[e]]=d[U]+dis;
                //fa[v[e]]=U;
                q.push(make_pair(d[v[e]],v[e]));
            }
        }

    }

    if(d[end]==INF)
        cout<<-1<<endl;
    else
        cout<<d[end]<<endl;

    return ;
}

int main()
{
    freopen("i.txt","r",stdin);
    //freopen("castle.in","r",stdin);
    //freopen("castle.out","w",stdout);
    int nCase,t,t1,t2,num=1;
    cin>>nCase;
    while(nCase--){
        //if(num!=1)
          //  cout<<endl;
        cout<<"Case "<<num++<<":"<<endl;
        l=0;
        cin>>n>>m>>k;
        memset(city,0,sizeof(city));
        memset(first,-1,sizeof(first));
        //memset(next,-1,sizeof(next));
        for(int i=0;i<k;i++){
            cin>>t;
            city[t]=1;
        }

        for(int i=0;i<m;i++){
            cin>>t1>>t2;
            u[l]=t1; v[l]=t2;
            next[l]=first[u[l]];
            first[u[l]]=l;
            ++l;

            u[l]=t2; v[l]=t1;
            next[l]=first[u[l]];
            first[u[l]]=l;
            ++l;
        }

        cin>>Q;
        for(int i=0;i<Q;i++){

            cin>>t1>>t2;

            work(t1,t2);
        }
        cout<<endl;
    }
    return 0;
}