BNUOJ-26480 Horror List 最短路

　　题目链接：http://www.bnuoj.com/bnuoj/problem_show.php?pid=26480

　　题意：简单来说，就是给一个图，然后从每个honor list中的点求最短路。。

　　边权值为1，Bfs就可以了，注意这里是无向图。。

 //STATUS:C++_AC_84MS_1788KB
 #include <functional>
 #include <algorithm>
 #include <iostream>
 //#include <ext/rope>
 #include <fstream>
 #include <sstream>
 #include <iomanip>
 #include <numeric>
 #include <cstring>
 #include <cassert>
 #include <cstdio>
 #include <string>
 #include <vector>
 #include <bitset>
 #include <queue>
 #include <stack>
 #include <cmath>
 #include <ctime>
 #include <list>
 #include <set>
 //#include <map>
 using namespace std;
 //#pragma comment(linker,"/STACK:102400000,102400000")
 //using namespace __gnu_cxx;
 //define
 #define pii pair<int,int>
 #define mem(a,b) memset(a,b,sizeof(a))
 #define lson l,mid,rt<<1
 #define rson mid+1,r,rt<<1|1
 #define PI acos(-1.0)
 //typedef
 typedef long long LL;
 typedef unsigned long long ULL;
 //const
 const int N=;
 const int INF=0x3f3f3f3f;
 const int MOD=1e9+,STA=;
 //const LL LNF=1LL<<60;
 const double EPS=1e-;
 const double OO=1e15;
 const int dx[]={-,,,};
 const int dy[]={,,,-};
 const int day[]={,,,,,,,,,,,,};
 //Daily Use ...
 inline int sign(double x){return (x>EPS)-(x<-EPS);}
 template<class T> T gcd(T a,T b){return b?gcd(b,a%b):a;}
 template<class T> T lcm(T a,T b){return a/gcd(a,b)*b;}
 template<class T> inline T lcm(T a,T b,T d){return a/d*b;}
 template<class T> inline T Min(T a,T b){return a<b?a:b;}
 template<class T> inline T Max(T a,T b){return a>b?a:b;}
 template<class T> inline T Min(T a,T b,T c){return min(min(a, b),c);}
 template<class T> inline T Max(T a,T b,T c){return max(max(a, b),c);}
 template<class T> inline T Min(T a,T b,T c,T d){return min(min(a, b),min(c,d));}
 template<class T> inline T Max(T a,T b,T c,T d){return max(max(a, b),max(c,d));}
 //End

 struct Edge{
     int u,v;
 }e[N**];
 int first[N],next[N**],vis[N],hig[N];
 int n,m,L,mt;

 void adde(int a,int b)
 {
     e[mt].u=a,e[mt].v=b;
     next[mt]=first[a],first[a]=mt++;
     e[mt].u=b,e[mt].v=a;
     next[mt]=first[b],first[b]=mt++;
 }

 queue<int> q;
 void bfs()
 {
     int i,j,u,v;
     while(!q.empty())
     {
         u=q.front();q.pop();
         for(i=first[u];i!=-;i=next[i]){
             v=e[i].v;
             if(vis[v])continue;
             vis[v]=;
             hig[v]=hig[u]+;
             q.push(v);
         }
     }
 }

 int main()
 {
  //   freopen("in.txt","r",stdin);
     int i,j,k,a,b,c;
     while(~scanf("%d%d%d",&n,&m,&L))
     {
         mem(first,-);mt=;
         mem(hig,INF);
         mem(vis,);
         for(i=;i<m;i++){
             scanf("%d",&a);
             hig[a]=;
             q.push(a);
             vis[a]=;
         }
         for(i=;i<L;i++){
             scanf("%d%d",&a,&b);
             adde(b,a);
         }

         bfs();
         int ans=,answ=;
         for(i=;i<n;i++){
             if(hig[i]>ans){
                 ans=hig[i];
                 answ=i;
             }
         }

         printf("%d\n",answ);
     }
     return ;
 }