【HDU】3335 Divisibility

 1 #include<cstdio>
 2 #include<algorithm>
 3 #define MAXM 1010
 4 #define MAXN 1000000
 5 #define INF 0x7FFFFFFF
 6 typedef long long LL;
 7 using namespace std;
 8 LL a[MAXM];
 9 int size, ans;
10 int L[MAXN], R[MAXN], U[MAXN], D[MAXN];
11 int H[MAXN], C[MAXN], S[MAXN];
12 void Init(int n) {
13     int i;
14     for (i = 0; i <= n; i++) {
15         R[i] = i + 1;
16         L[i + 1] = i;
17         U[i] = D[i] = i;
18         S[i] = 0;
19         H[i] = -1;
20     }
21     R[n] = 0;
22     size = n + 1;
23 }
24 void Link(int r, int c) {
25     D[size] = D[c];
26     U[size] = c;
27     U[D[c]] = size;
28     D[c] = size;
29     if (H[r] < 0)
30         H[r] = L[size] = R[size] = size;
31     else {
32         L[size] = H[r];
33         R[size] = R[H[r]];
34         L[R[H[r]]] = size;
35         R[H[r]] = size;
36     }
37     S[c]++;
38     C[size++] = c;
39 }
40 int A() {
41     int i, res;
42     for (res = 0, i = R[0]; i; i = R[i])
43         res++;
44     return res;
45 }
46 void Remove(int c) {
47     int i;
48     for (i = D[c]; i != c; i = D[i]) {
49         L[R[i]] = L[i];
50         R[L[i]] = R[i];
51     }
52 }
53 void Resume(int c) {
54     int i;
55     for (i = D[c]; i != c; i = D[i])
56         L[R[i]] = R[L[i]] = i;
57 }
58 void Dance(int now) {
59     if (R[0] == 0)
60         ans = max(ans, now);
61     else if (now + A() > ans) {
62         int i, j, temp, c;
63         for (temp = INF,i = R[0]; i; i = R[i]) {
64             if (temp > S[i]) {
65                 temp = S[i];
66                 c = i;
67             }
68         }
69         for (i = D[c]; i != c; i = D[i]) {
70             Remove(i);
71             for (j = R[i]; j != i; j = R[j])
72                 Remove(j);
73             Dance(now + 1);
74             for (j = L[i]; j != i; j = L[j])
75                 Resume(j);
76             Resume(j);
77         }
78     }
79 }
80 int main() {
81     int c, i, j, n;
82     scanf("%d", &c);
83     while (c--) {
84         scanf("%d", &n);
85         Init(n);
86         for (i = 1; i <= n; i++)
87             scanf("%I64d", &a[i]);
88         for (i = 1; i <= n; i++) {
89             for (j = 1; j <= n; j++) {
90                 if (a[i] % a[j] == 0 || a[j] % a[i] == 0)
91                     Link(i, j);
92             }
93         }
94         ans = 0;
95         Dance(0);
96         printf("%d\n", ans);
97     }
98     return 0;
99 }