【HDOJ】Power Stations

DLX。针对每个城市，每个城市可充电的区间构成一个plan。每个决策由N*D个时间及N个精确覆盖构成。

 /* 3663 */
 #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

 const int maxn = ;
 const int maxe = ;
 int B[maxn];
 int S[maxn], E[maxn];
 int ut[maxn], vt[maxn];
 int N, M, D;
 int adj[maxn][maxn];
 int arr[maxn];

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

     int n, sz;
     int S[maxc];

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

     int bound;
     int ansd, ans[maxr];

     void init(int bound_, int n_) {
         bound = bound_;
         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 first = sz;
         int size = SZ(columns);

         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;
         }

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

     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[]== || R[]>bound) {
             ansd = d;
             return true;
         }

         int c = R[];
         for (int i=R[]; i!=&&i<=bound; 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;
     }

 } DLX;

 DLX solver;

 int encode(int index, int s, int e) {
     return (index<<) + (s<<)+e;
 }

 void decode(int code, int& index, int& s, int& e) {
     e = code & ;
     code >>= ;
     s = code & ;
     code >>= ;
     index = code;
 }

 void solve() {
     int nd = N*D;
     solver.init(nd, nd+N);

     B[] = ;
     rep(i, , N+)
         B[i] = B[i-]+D;

     rep(i, , N+) {
         int s = S[i];
         int e = E[i];
         int m = ;
         rep(j, , N+) {
             if (adj[i][j])
                 arr[m++] = j;
         }

         rep(ss, s, e+) {
             rep(ee, ss, e+) {
                 vi columns;
                 rep(k, , m) {
                     int v = arr[k];
                     rep(j, ss, ee+)
                         columns.pb(B[v] + j);
                 }
                 columns.pb(nd + i);
                 solver.addRow(encode(i, ss, ee), columns);
             }
         }
     }

     bool flag = solver.dfs();
     if (flag) {
         memset(ut, , sizeof(ut));
         memset(vt, , sizeof(vt));
         int s, e, index;
         rep(i, , solver.ansd) {
             decode(solver.ans[i], index, s, e);
             ut[index] = s;
             vt[index] = e;
         }
         rep(i, , N+)
             printf("%d %d\n", ut[i], vt[i]);
     } else {
         puts("No solution");
     }
     putchar('\n');
 }

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

     int u, v;

     while (scanf("%d %d %d",&N,&M,&D)!=EOF) {
         memset(adj, false, sizeof(adj));
         rep(i, , M) {
             scanf("%d %d", &u, &v);
             adj[u][v] = adj[v][u] = true;
         }
         rep(i, , N+)
             adj[i][i] = true;
         rep(i, , N+) {
             scanf("%d %d", &S[i], &E[i]);
         }
         solve();
     }

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

     return ;
 }