hdu 4069 福州赛区网络赛I DLC ***

再遇到一个DLC就刷个专题

 #include <stdio.h>
 #include <string.h>
 #include <iostream>
 #include <algorithm>
 #include <vector>
 #include <queue>
 #include <set>
 #include <map>
 #include <string>
 #include <math.h>
 #include <stdlib.h>
 #include <time.h>
 using namespace std;
 const int N = ; //3*3数独
 const int MaxN = N*N*N + ;
 const int MaxM = N*N* + ;
 const int maxnode = MaxN* + MaxM + ;
 char g[MaxN];
 int cnt;
 struct DLX
 {
     int n,m,size;
     int U[maxnode],D[maxnode],R[maxnode],L[maxnode],Row[maxnode],Col[maxnode];
     int H[MaxN],S[MaxM];
     int ansd,ans[MaxN];
     void init(int _n,int _m)
     {
         n = _n;
         m = _m;
         for(int i = ;i <= m;i++)
         {
             S[i] = ;
             U[i] = D[i] = i;
             L[i] = i-;
             R[i] = i+;
         }
         R[m] = ; L[] = m;
         size = m;
         for(int i = ;i <= n;i++)H[i] = -;
     }
     void Link(int r,int c)
     {
         ++S[Col[++size]=c];
         Row[size] = r;
         D[size] = D[c];
         U[D[c]] = size;
         U[size] = c;
         D[c] = size;
         if(H[r] < )H[r] = L[size] = R[size] = size;
         else
         {
             R[size] = R[H[r]];
             L[R[H[r]]] = size;
             L[size] = H[r];
             R[H[r]] = size;
         }
     }
     void remove(int c)
     {
         L[R[c]] = L[c]; R[L[c]] = R[c];
         for(int i = D[c];i != c;i = D[i])
             for(int j = R[i];j != i;j = R[j])
             {
                 U[D[j]] = U[j];
                 D[U[j]] = D[j];
                 --S[Col[j]];
             }
     }
     void resume(int c)
     {
         for(int i = U[c];i != c;i = U[i])
             for(int j = L[i];j != i;j = L[j])
                 ++S[Col[U[D[j]]=D[U[j]]=j]];
         L[R[c]] = R[L[c]] = c;
     }
     void Dance(int d)
     {
         if(cnt > )return;
         if(R[] == )
         {
             for(int i = ;i < d;i++)g[(ans[i]-)/] = (ans[i]-)% + '';
             cnt++;
             return;
         }
         int c = R[];
         for(int i = R[];i != ;i = R[i])
             if(S[i] < S[c])
                 c = i;
         remove(c);
         for(int i = D[c];i != c;i = D[i])
         {
             ans[d] = Row[i];
             for(int j = R[i];j != i;j = R[j])remove(Col[j]);
             Dance(d+);
             if(cnt > )return;
             for(int j = L[i];j != i;j = L[j])resume(Col[j]);
         }
         resume(c);
     }
 };

 int id[][];
 int a[][];
 void bfs(int sx,int sy,int d)
 {
     queue<pair<int,int> >q;
     q.push(make_pair(sx,sy));
     id[sx][sy] = d;
     while(!q.empty())
     {
         pair<int,int> tmp = q.front();
         int x = tmp.first;
         int y = tmp.second;
         q.pop();
         if(x >  && ((a[x][y]%)/) == )
             if(id[x-][y] == -)
             {
                 id[x-][y] = d;
                 q.push(make_pair(x-,y));
             }
         if(x < N- && ((a[x][y]%)/) == )
             if(id[x+][y] == -)
             {
                 id[x+][y] = d;
                 q.push(make_pair(x+,y));
             }
         if(y >  && ((a[x][y])/) == )
             if(id[x][y-] == -)
             {
                 id[x][y-] = d;
                 q.push(make_pair(x,y-));
             }
         if(y < N- && ((a[x][y]%)/) == )
             if(id[x][y+] == -)
             {
                 id[x][y+] = d;
                 q.push(make_pair(x,y+));
             }
     }
 }
 DLX dlx;

 int main()
 {
     //freopen("in.txt","r",stdin);
     //freopen("out.txt","w",stdout);
     int T;
     scanf("%d",&T);
     int iCase = ;
     while(T--)
     {
         iCase++;
         for(int i = ;i < N;i++)
             for(int j = ;j < N;j++)
                 scanf("%d",&a[i][j]);
         memset(id,-,sizeof(id));
         int index = ;
         for(int i = ;i < N;i++)
             for(int j = ;j < N;j++)
                 if(id[i][j] == -)
                     bfs(i,j,++index);
         dlx.init(N*N*N,N*N*);
         for(int i = ;i < N;i++)
             for(int j = ;j < N;j++)
                 for(int k = ;k <= N;k++)
                 {
                     if(a[i][j]% !=  && a[i][j]% != k)continue;
                     int r = (i*N+j)*N + k;
                     int c1 = i*N+j+;
                     int c2 = N*N+i*N+k;
                     int c3 = N*N*+j*N+k;
                     int c4 = N*N*+(id[i][j]-)*N+k;
                     dlx.Link(r,c1);
                     dlx.Link(r,c2);
                     dlx.Link(r,c3);
                     dlx.Link(r,c4);
                 }
         cnt = ;
         dlx.Dance();
         printf("Case %d:\n",iCase);
         if(cnt == )printf("No solution\n");
         else if(cnt > )printf("Multiple Solutions\n");
         else
         {
             for(int i = ;i < N*N;i++)
             {
                 printf("%c",g[i]);
                 if(i % N == N - )
                     printf("\n");
             }
         }
     }
     return ;
 }