51Nod 1134 最长递增子序列（动态规划O(nlogn)）

 #include <iostream>
 #include <algorithm>
 #include <stdio.h>
 #define MAXN 50010
 using namespace std;

 const int MIN = -1e9;

 int main(void){
     int n, a[MAXN], vis[MAXN], len = ;
     scanf("%d", &n);
     for (int i = ; i<n; i++){
         scanf("%d", &a[i]);
     }
     for (int i = ; i <= n; i++){
         vis[i] = MIN;
     }

     //vis[i]表示满足递增数量i的最小值
     vis[] = a[];
     for (int i = ; i<n; i++){
         //upper_bound(vis + 1, vis + len + 1, a[i]) 返回被查序列中第一个大于查找值的指针
         int pos = upper_bound(vis + , vis + len + , a[i]) - vis;
         vis[pos] = a[i];
         if (len<pos){ //维护最大长度
             len = pos;
         }
     }
     printf("%d\n", len);
     return ;
 }