【ZOJ】3209 Treasure Map

  1 #include<cstdio>

  2 #include<algorithm>

  3 #define INF 0x7FFFFFFF

  4 #define MAXN 450010

  5 using namespace std;

  6 int L[MAXN], R[MAXN], U[MAXN], D[MAXN], H[MAXN];

  7 int n, m, p, size, ans, C[MAXN], S[MAXN];

  8 void Init() {

  9     int i;

 10     n *= m;

 11     for (i = 0; i <= n; i++) {

 12         S[i] = 0;

 13         L[i + 1] = i;

 14         R[i] = i + 1;

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

 16     }

 17     R[n] = 0;

 18     size = n + 1;

 19 }

 20 void Remove(int c) {

 21     int i, j;

 22     L[R[c]] = L[c];

 23     R[L[c]] = R[c];

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

 25         for (j = R[i]; j != i; j = R[j]) {

 26             U[D[j]] = U[j];

 27             D[U[j]] = D[j];

 28             S[C[j]]--;

 29         }

 30     }

 31 }

 32 void Resume(int c) {

 33     int i, j;

 34     L[R[c]] = c;

 35     R[L[c]] = c;

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

 37         for (j = R[i]; j != i; j = R[j]) {

 38             U[D[j]] = j;

 39             D[U[j]] = j;

 40             S[C[j]]++;

 41         }

 42     }

 43 }

 44 inline void Link(int r, int c) {

 45     U[size] = c;

 46     D[size] = D[c];

 47     U[D[c]] = size;

 48     D[c] = size;

 49     if (H[r] < 0)

 50         H[r] = L[size] = R[size] = size;

 51     else {

 52         L[size] = H[r];

 53         R[size] = R[H[r]];

 54         L[R[H[r]]] = size;

 55         R[H[r]] = size;

 56     }

 57     S[c]++;

 58     C[size++] = c;

 59 }

 60 void Dance(int now) {

 61     if (R[0] == 0)

 62         ans = min(ans, now);

 63     else {

 64         int i, j, c, temp;

 65         for (temp = INF,i = R[0]; i; i = R[i]) {

 66             if (S[i] < temp) {

 67                 c = i;

 68                 temp = S[i];

 69             }

 70         }

 71         Remove(c);

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

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

 74                 Remove(C[j]);

 75             Dance(now + 1);

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

 77                 Resume(C[j]);

 78         }

 79         Resume(c);

 80     }

 81 }

 82 int main() {

 83     int c, i, j, k, x1, y1, x2, y2;

 84     scanf("%d", &c);

 85     while (c--) {

 86         scanf("%d%d%d", &n, &m, &p);

 87         Init();

 88         for (i = 1; i <= p; i++) {

 89             H[i] = -1;

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

 91             for (j = x1 + 1; j <= x2; j++) {

 92                 for (k = y1 + 1; k <= y2; k++)

 93                     Link(i, (j - 1) * m + k);

 94             }

 95         }

 96         ans = INF;

 97         Dance(0);

 98         if (ans != INF)

 99             printf("%d\n", ans);

100         else

101             puts("-1");

102     }

103     return 0;

104 }