POJ2533Longest Ordered Subsequence（DP）

http://poj.org/problem?id=2533

在经典不过的DP题目了。。。。

 #include <map>
 #include <set>
 #include <stack>
 #include <queue>
 #include <cmath>
 #include <ctime>
 #include <vector>
 #include <cstdio>
 #include <cctype>
 #include <cstring>
 #include <cstdlib>
 #include <iostream>
 #include <algorithm>
 using namespace std;
 #define INF 0x3f3f3f3f
 #define MAX(a,b) (a > b ? a : b)
 #define MIN(a,b) (a < b ? a : b)
 #define mem0(a) memset(a,0,sizeof(a))

 typedef long long LL;
 const double eps = 1e-;
 const int MAXN = ;
 const int MAXM = ;

 int DP[], a[], N;

 int BinarySearch(int low, int high, int val)
 {
     while(low < high)
     {
         int mid = (low + high) >> ;
         if(DP[mid] < val) low = mid +;
         else high = mid;
     }
     return low;
 }

 int main()
 {
     while(~scanf("%d", &N))
     {
         for(int i=;i<=N;i++)
         {
             scanf("%d", &a[i]);
         }
         DP[] = a[];
         int len = ;
         for(int i=;i<=N;i++)
         {
             int id = BinarySearch(, len+, a[i]);
             DP[id] = a[i];
             if(id > len) ++len;
         }
         printf("%d\n", len);
     }
     return ;
 }