HDU-4678 Mine 博弈SG函数

  题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4678

  题意就不说了,太长了。。。

  这个应该算简单博弈吧。先求联通分量,把空白区域边上的数字个数全部求出来a[i](就是一个连通分量),然后就是n堆石子,每堆每次可以取一个或者全部取掉,然后要注意在取玩边上的石子后,剩下的就只能一次取掉了,因此我们直接把空白区域上的算做一个a[i]+1。然后这个SG函数很好求,奇数是1,偶数是2。。。

  1 //STATUS:C++_AC_156MS_4268KB
  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 __int64 LL;
 34 typedef unsigned __int64 ULL;
 35 //const
 36 const int N=1010;
 37 const int INF=0x3f3f3f3f;
 38 const LL MOD=1000000007,STA=8000010;
 39 const LL LNF=1LL<<55;
 40 const double EPS=1e-9;
 41 const double OO=1e50;
 42 const int dx[8]={-1,-1,0,1,1,1,0,-1};
 43 const int dy[8]={0,1,1,1,0,-1,-1,-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 int g[N][N];
 59 int T,n,m,k;
 60 
 61 int bfs(int x,int y)
 62 {
 63     int i,nx,ny,ret=0;
 64     pii t;
 65     g[x][y]=-1;
 66     queue<pii> q;
 67     q.push(make_pair(x,y));
 68     while(!q.empty())
 69     {
 70         t=q.front();q.pop();
 71         for(i=0;i<8;i++){
 72             nx=t.first+dx[i];
 73             ny=t.second+dy[i];
 74             if(nx<0||nx>=n || ny<0||ny>=m || g[nx][ny]==-1)continue;
 75             if(g[nx][ny])ret++;
 76             else q.push(make_pair(nx,ny));
 77             g[nx][ny]=-1;
 78         }
 79     }
 80     return ret;
 81 }
 82 
 83 int main(){
 84  //   freopen("in.txt","r",stdin);
 85     int i,j,sg,x,y,nx,ny,ca=1;
 86     scanf("%d",&T);
 87     while(T--)
 88     {
 89         scanf("%d%d%d",&n,&m,&k);
 90         mem(g,0);
 91         for(i=0;i<k;i++){
 92             scanf("%d%d",&x,&y);
 93             g[x][y]=-1;
 94             for(j=0;j<8;j++){
 95                 nx=x+dx[j];ny=y+dy[j];
 96                 if(nx<0||nx>=n || ny<0||ny>=m || g[nx][ny]==-1)continue;
 97                 g[nx][ny]=1;
 98             }
 99         }
100 
101         sg=0;
102         for(i=0;i<n;i++){
103             for(j=0;j<m;j++){
104                 if(g[i][j])continue;
105                 sg^=(bfs(i,j)&1)+1;
106             }
107         }
108         for(i=0;i<n;i++){
109             for(j=0;j<m;j++){
110                 if(g[i][j]==-1)continue;
111                 sg^=1;
112             }
113         }
114 
115         printf("Case #%d: %s
",ca++,sg?"Xiemao":"Fanglaoshi");
116     }
117     return 0;
118 }
原文地址:https://www.cnblogs.com/zhsl/p/3263675.html