【HDOJ】4210 Su-domino-ku

DLX。在模板的基础上增加一个FILL属性，略修改即可。

 /* 4210 */
 #include <iostream>
 #include <string>
 #include <map>
 #include <queue>
 #include <set>
 #include <stack>
 #include <vector>
 #include <deque>
 #include <algorithm>
 #include <cstdio>
 #include <cmath>
 #include <ctime>
 #include <cstring>
 #include <climits>
 #include <cctype>
 #include <cassert>
 #include <functional>
 #include <iterator>
 #include <iomanip>
 using namespace std;
 //#pragma comment(linker,"/STACK:102400000,1024000")

 #define sti                set<int>
 #define stpii            set<pair<int, int> >
 #define mpii            map<int,int>
 #define vi                vector<int>
 #define pii                pair<int,int>
 #define vpii            vector<pair<int,int> >
 #define rep(i, a, n)     for (int i=a;i<n;++i)
 #define per(i, a, n)     for (int i=n-1;i>=a;--i)
 #define clr                clear
 #define pb                 push_back
 #define mp                 make_pair
 #define fir                first
 #define sec                second
 #define all(x)             (x).begin(),(x).end()
 #define SZ(x)             ((int)(x).size())
 #define lson            l, mid, rt<<1
 #define rson            mid+1, r, rt<<1|1

 typedef struct {
     static const int maxc = **+;
     static const int maxr = ;
     static const int maxn = maxr * maxc;

     int n, sz;
     int S[maxc];

     int row[maxn], col[maxn];
     int L[maxn], R[maxn], U[maxn], D[maxn];

     int ansd, ans[maxr];

     void init(int n_) {
         n = n_;

         rep(i, , n+) {
             L[i] = i - ;
             R[i] = i + ;
             U[i] = i;
             D[i] = i;
             col[i] = i;
         }

         L[] = n;
         R[n] = ;

         sz = n + ;
         memset(S, , sizeof(S));
     }

     void addRow(int r, vi columns) {
         int size = SZ(columns);
         int first = sz;

         rep(i, , size) {
             int c = columns[i];

             L[sz] = sz - ;
             R[sz] = sz + ;

             D[sz] = c;
             U[sz] = U[c];
             D[U[c]] = sz;
             U[c] = sz;

             row[sz] = r;
             col[sz] = c;

             ++S[c];
             ++sz;
         }

         R[sz-] = first;
         L[first] = sz-;
     }

     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 restore(int c) {
         L[R[c]] = c;
         R[L[c]] = c;
         for (int i=D[c]; i!=c; i=D[i]) {
             for (int j=R[i]; j!=i; j=R[j]) {
                 U[D[j]] = j;
                 D[U[j]] = j;
                 ++S[col[j]];
             }
         }
     }

     bool dfs(int d) {
         if (R[] == ) {
             ansd = d;
             return true;
         }

         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]);
             }
             if(dfs(d + ))    return true;
             for (int j=L[i]; j!=i; j=L[j]) {
                 restore(col[j]);
             }
         }
         restore(c);

         return false;
     }

     void solve(vi& v) {
         v.clr();

         dfs();

         rep(i, , ansd)
             v.pb(ans[i]);
     }

 } DLX;

 typedef struct {
     int a, b;
     int r, c;
     int d;
 } node_t;

 const int SLOT = ;
 const int ROW = ;
 const int COL = ;
 const int SUB = ;
 const int FILL = ;
 const int maxn = ;
 int M[][];
 bool mark[][];
 DLX solver;
 node_t nd[maxn];
 int rn;
 vi ans;

 int encode(int a, int b, int c) {
     return a* + b* + c+;
 }

 void decode(int code, int& a, int& b, int& c) {
     --code;
     c = code % ;
     code /= ;
     b = code % ;
     code /= ;
     a = code;
 }

 void init() {
     rn = ;
     memset(mark, false, sizeof(mark));
 }

 void input(int n) {
     int r, c;
     int x1, x2;
     char ps1[], ps2[], ps[];

     solver.init(**);
     init();
     rep(i, , n) {
         scanf("%d %s %d %s", &x1, ps1, &x2, ps2);
         vi columns;

         // handle 1-st
         r = ps1[]-'A';
         c = ps1[]-'';
         --x1;
         columns.pb(encode(SLOT, r, c));
         columns.pb(encode(ROW, r, x1));
         columns.pb(encode(COL, c, x1));
         columns.pb(encode(SUB, r/*+c/, x1));
         M[r][c] = x1;

         // handle 2-nd
         r = ps2[]-'A';
         c = ps2[]-'';
         --x2;
         columns.pb(encode(SLOT, r, c));
         columns.pb(encode(ROW, r, x2));
         columns.pb(encode(COL, c, x2));
         columns.pb(encode(SUB, r/*+c/, x2));
         M[r][c] = x2;

         mark[x1][x2] = mark[x2][x1] = true;
         columns.pb(encode(FILL, x1, x2));
         columns.pb(encode(FILL, x2, x1));
         solver.addRow(rn++, columns);
     }
     rep(i, , ) {
         scanf("%s", ps);
         r = ps[]-'A';
         c = ps[]-'';
         M[r][c] = i;
         mark[i][i] = true;
         vi columns;
         columns.pb(encode(SLOT, r, c));
         columns.pb(encode(ROW, r, i));
         columns.pb(encode(COL, c, i));
         columns.pb(encode(SUB, r/*+c/, i));
         columns.pb(encode(FILL, i, i));
         solver.addRow(rn++, columns);
     }
     rep(i, , ) {
         rep(j, , ) {
             if (mark[i][j])
                 continue;
             for (r=; r<=; ++r) {
                 for (c=; c<; ++c) {
                     nd[rn].a = i;
                     nd[rn].b = j;
                     nd[rn].d = ;
                     nd[rn].r = r;
                     nd[rn].c = c;

                     vi columns;
                     columns.pb(encode(SLOT, r, c));
                     columns.pb(encode(ROW, r, i));
                     columns.pb(encode(COL, c, i));
                     columns.pb(encode(SUB, r/*+c/, i));
                     int cc = c + ;
                     columns.pb(encode(SLOT, r, cc));
                     columns.pb(encode(ROW, r, j));
                     columns.pb(encode(COL, cc, j));
                     columns.pb(encode(SUB, r/*+cc/, j));
                     columns.pb(encode(FILL, i, j));
                     columns.pb(encode(FILL, j, i));
                     solver.addRow(rn++, columns);
                 }
             }

             for(r=; r<; ++r) {
                 int rr = r + ;
                 for (c=; c<=; ++c) {
                     nd[rn].a = i;
                     nd[rn].b = j;
                     nd[rn].d = ;
                     nd[rn].r = r;
                     nd[rn].c = c;

                     vi columns;
                     columns.pb(encode(SLOT, r, c));
                     columns.pb(encode(ROW, r, i));
                     columns.pb(encode(COL, c, i));
                     columns.pb(encode(SUB, r/*+c/, i));
                     columns.pb(encode(SLOT, rr, c));
                     columns.pb(encode(ROW, rr, j));
                     columns.pb(encode(COL, c, j));
                     columns.pb(encode(SUB, rr/*+c/, j));
                     columns.pb(encode(FILL, i, j));
                     columns.pb(encode(FILL, j, i));
                     solver.addRow(rn++, columns);
                 }
             }
         }
     }
 }

 void solve(int n) {
     solver.solve(ans);
     int sz = SZ(ans), id;
     n += ;

     rep(i, , sz) {
         if (ans[i] > n) {
             id = ans[i];
             if (nd[id].d) {
                 M[nd[id].r][nd[id].c] = nd[id].a;
                 M[nd[id].r+][nd[id].c] = nd[id].b;
             } else {
                 M[nd[id].r][nd[id].c] = nd[id].a;
                 M[nd[id].r][nd[id].c+] = nd[id].b;
             }
         }
     }

     rep(i, , ) {
         rep(j, , ) {
             ++M[i][j];
             printf("%d", M[i][j]);
         }
         putchar('\n');
     }
 }

 int main() {
     ios::sync_with_stdio(false);
     #ifndef ONLINE_JUDGE
         freopen("data.in", "r", stdin);
         freopen("data.out", "w", stdout);
     #endif

     int n;
     int t = ;

     while (scanf("%d",&n)!=EOF && n) {
         memset(mark, false, sizeof(mark));
         input(n);
         printf("Puzzle %d\n", ++t);
         solve(n);
     }

     #ifndef ONLINE_JUDGE
         printf("time = %d.\n", (int)clock());
     #endif

     return ;
 }