poj1631 Bridging signals

Posted 2020-09-05 王宜鸣

思路：

LIS，二分。

实现：

 1 #include <cstdio>
 2 #include <iostream>
 3 using namespace std;
 4 int d[40010];
 5 int fuck(int x, int right)
 6 {
 7     int left = 0;
 8     int pos = -1;
 9     while (left <= right)
10     {
11         int middle = (left + right) / 2;
12         if (d[middle] >= x)
13         {
14             pos = middle;
15             right = middle - 1;
16         }
17         else
18         {
19             left = middle + 1;
20         }
21     }
22     return pos;
23 }
24 int main()
25 {
26     int t, n;
27     int temp;
28     cin >> t;
29     while (t--)
30     {
31         cin >> n;
32         int cnt = 0;
33         for (int i = 0; i < n; i++)
34         {
35             scanf("%d", &temp);
36             if (cnt == 0 || temp > d[cnt - 1])
37             {
38                 d[cnt++] = temp;
39             }
40             else
41             {
42                 int pos = fuck(temp, cnt - 1);
43                 d[pos] = temp;
44             }
45         }
46         printf("%d\n", cnt);
47     }
48     return 0;
49 }