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。。

  1 //STATUS:C++_AC_84MS_1788KB
  2 #include <functional>
  3 #include <algorithm>
  4 #include <iostream>
  5 //#include <ext/rope>
  6 #include <fstream>
  7 #include <sstream>
  8 #include <iomanip>
  9 #include <numeric>
 10 #include <cstring>
 11 #include <cassert>
 12 #include <cstdio>
 13 #include <string>
 14 #include <vector>
 15 #include <bitset>
 16 #include <queue>
 17 #include <stack>
 18 #include <cmath>
 19 #include <ctime>
 20 #include <list>
 21 #include <set>
 22 //#include <map>
 23 using namespace std;
 24 //#pragma comment(linker,"/STACK:102400000,102400000")
 25 //using namespace __gnu_cxx;
 26 //define
 27 #define pii pair<int,int>
 28 #define mem(a,b) memset(a,b,sizeof(a))
 29 #define lson l,mid,rt<<1
 30 #define rson mid+1,r,rt<<1|1
 31 #define PI acos(-1.0)
 32 //typedef
 33 typedef long long LL;
 34 typedef unsigned long long ULL;
 35 //const
 36 const int N=1010;
 37 const int INF=0x3f3f3f3f;
 38 const int MOD=1e9+7,STA=8000010;
 39 //const LL LNF=1LL<<60;
 40 const double EPS=1e-8;
 41 const double OO=1e15;
 42 const int dx[4]={-1,0,1,0};
 43 const int dy[4]={0,1,0,-1};
 44 const int day[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};
 45 //Daily Use ...
 46 inline int sign(double x){return (x>EPS)-(x<-EPS);}
 47 template<class T> T gcd(T a,T b){return b?gcd(b,a%b):a;}
 48 template<class T> T lcm(T a,T b){return a/gcd(a,b)*b;}
 49 template<class T> inline T lcm(T a,T b,T d){return a/d*b;}
 50 template<class T> inline T Min(T a,T b){return a<b?a:b;}
 51 template<class T> inline T Max(T a,T b){return a>b?a:b;}
 52 template<class T> inline T Min(T a,T b,T c){return min(min(a, b),c);}
 53 template<class T> inline T Max(T a,T b,T c){return max(max(a, b),c);}
 54 template<class T> inline T Min(T a,T b,T c,T d){return min(min(a, b),min(c,d));}
 55 template<class T> inline T Max(T a,T b,T c,T d){return max(max(a, b),max(c,d));}
 56 //End
 57 
 58 struct Edge{
 59     int u,v;
 60 }e[N*10*2];
 61 int first[N],next[N*10*2],vis[N],hig[N];
 62 int n,m,L,mt;
 63 
 64 void adde(int a,int b)
 65 {
 66     e[mt].u=a,e[mt].v=b;
 67     next[mt]=first[a],first[a]=mt++;
 68     e[mt].u=b,e[mt].v=a;
 69     next[mt]=first[b],first[b]=mt++;
 70 }
 71 
 72 queue<int> q;
 73 void bfs()
 74 {
 75     int i,j,u,v;
 76     while(!q.empty())
 77     {
 78         u=q.front();q.pop();
 79         for(i=first[u];i!=-1;i=next[i]){
 80             v=e[i].v;
 81             if(vis[v])continue;
 82             vis[v]=1;
 83             hig[v]=hig[u]+1;
 84             q.push(v);
 85         }
 86     }
 87 }
 88 
 89 int main()
 90 {
 91  //   freopen("in.txt","r",stdin);
 92     int i,j,k,a,b,c;
 93     while(~scanf("%d%d%d",&n,&m,&L))
 94     {
 95         mem(first,-1);mt=0;
 96         mem(hig,INF);
 97         mem(vis,0);
 98         for(i=0;i<m;i++){
 99             scanf("%d",&a);
100             hig[a]=0;
101             q.push(a);
102             vis[a]=1;
103         }
104         for(i=0;i<L;i++){
105             scanf("%d%d",&a,&b);
106             adde(b,a);
107         }
108 
109         bfs();
110         int ans=0,answ=0;
111         for(i=0;i<n;i++){
112             if(hig[i]>ans){
113                 ans=hig[i];
114                 answ=i;
115             }
116         }
117 
118         printf("%d\n",answ);
119     }
120     return 0;
121 }

 

posted @ 2013-08-26 10:21  zhsl  阅读(274)  评论(0编辑  收藏  举报