ZOJ 3209 Treasure Map 精确覆盖

题目链接

精确覆盖的模板题， 把每一个格子当成一列就可以。

S忘记初始化TLE N次， 哭晕在厕所......

 #include<bits/stdc++.h>

 using namespace std;

 #define pb(x) push_back(x)

 #define ll long long

 #define mk(x, y) make_pair(x, y)

 #define lson l, m, rt<<1

 #define mem(a) memset(a, 0, sizeof(a))

 #define rson m+1, r, rt<<1|1

 #define mem1(a) memset(a, -1, sizeof(a))

 #define mem2(a) memset(a, 0x3f, sizeof(a))

 #define rep(i, a, n) for(int i = a; i<n; i++)

 #define ull unsigned long long

 typedef pair<int, int> pll;

 const double PI = acos(-1.0);

 const double eps = 1e-;

 const int mod = 1e9+;

 const int inf = ;

 const int dir[][] = { {-, }, {, }, {, -}, {, } };

 const int maxn = ;

 const int maxNode = ;

 struct DLX {

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

     int S[maxn], H[maxn], deep, sz, n, m, num;

     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[j]]++;

                 D[U[j]] = j;

                 U[D[j]] = j;

             }

         R[L[c]] = c;

         L[R[c]] = c;

     }

     void dfs(int d) {

         if(d>=deep)

             return ;

         if(R[] == ) {

             deep = min(d, deep);

             return ;

         }

         int c = R[];

         for(int i = R[]; i!=; i = R[i])

             if(S[c]>S[i])

                 c = i;

         remove(c);

         for(int i = D[c]; i!=c; i = D[i]) {

             for(int j = R[i]; j!=i; j = R[j])

                 remove(col[j]);

             dfs(d+);

             for(int j = L[i]; j!=i; j = L[j])

                 resume(col[j]);

         }

         resume(c);

         return ;

     }

     void add(int r, int c) {

         sz++;

         col[sz] = c;

         S[c]++;

         U[sz] = U[c];

         D[sz] = c;

         D[U[c]] = sz;

         U[c] = sz;

         if(~H[r]) {

             R[sz] = H[r];

             L[sz] = L[H[r]];

             L[R[sz]] = sz;

             R[L[sz]] = sz;

         } else {

             H[r] = L[sz] = R[sz] = sz;

         }

     }

     void init(){

         mem1(H);

         for(int i = ; i<=n; i++) {

             R[i] = i+;

             L[i] = i-;

             D[i] = U[i] = i;

         }

         R[n] = ;

         L[] = n;

         mem(S);

         sz = n;

         deep = inf;

     }

     void solve() {

         scanf("%d%d%d", &n, &m, &num);

         n *= m;

         init();

         int x1, y1, x2, y2;

         int cnt = ;

         while(num--) {

             scanf("%d%d%d%d", &x1, &y1, &x2, &y2);

             for(int i = x1+; i<=x2; i++) {

                 for(int j = y1+; j<=y2; j++) {

                     add(cnt, (i-)*m+j);

                 }

             }

             cnt++;

         }

         dfs();

         if(deep == inf) {

             puts("-1");

         } else {

             printf("%d\n", deep);

         }

     }

 }dlx;

 int main()

 {

     int t;

     cin>>t;

     while(t--) {

         dlx.solve();

     }

 }