POJ 1631 Bridging signals（LIS+二分）

 1 /*
 2 ** POJ 1631 Bridging signals
 3 ** Created by Rayn @@ 2014/05/06
 4 ** 最长上升子序列
 5 */
 6 #include <cstdio>
 7 #include <cstring>
 8 #include <algorithm>
 9 using namespace std;
10 const int MAX = 40010;
11 
12 int ans, arr[MAX], dp[MAX];
13 
14 int main()
15 {
16 #ifdef _Rayn
17     freopen("in.txt", "r", stdin);
18 #endif
19 
20     int t, n;
21 
22     scanf("%d", &t);
23     while(t--)
24     {
25         scanf("%d", &n);
26         for(int i=1; i<=n; ++i)
27             scanf("%d", &arr[i]);
28 
29         memset(dp, 0, sizeof(dp));
30         ans = 0;
31         dp[ans++] = arr[1];
32         for(int i=2; i<=n; ++i)
33         {
34             if(arr[i] > dp[ans-1])
35             {
36                 dp[ans++] = arr[i];
37             }
38             else
39             {
40                 int *p = lower_bound(dp, dp+ans, arr[i]);
41                 *p = arr[i];
42             }
43         }
44         printf("%d\n", ans);
45     }
46     return 0;
47 }