HDU 1025 最长上升子序列(nlogn)

题目:http://acm.hdu.edu.cn/showproblem.php?pid=1025

第一次写最长上升子序列不是写的这题,所以对于这个最长上升子序列的模板题也没什么好说的,主要坑点在于,如果答案是一road用单数..............

 //Must so
 #include<bits/stdc++.h>
 #define mem(a,x) memset(a,x,sizeof(a))
 #define sqrt(n) sqrt((double)n)
 #define pow(a,b) pow((double)a,(int)b)
 #define inf (1<<29)
 #define NN 100005
 using namespace std;
 const double PI = acos(-1.0);
 typedef long long LL;

 /*
     Name: HDU 1025
     Copyright:
     Author: Must so
     Date: 24/03/16 10:30
     Description: 最长上升子序列

     定义d[k]:长度为k的上升序列最末元素(终点元素)
     //注意d中元素是单调递增的
     初始化:len = 1,d[1]=a[1],
     然后对于a[i]:
         if a[i] > d[len]
             len++,d[len] = a[i]
         else
              from d[1] to d[len]找到一个j
              满足 d[j-1]<a[i]<d[j]
              更新d[j] = a[i]
 */

 int d[NN],a[NN];
 int main()
 {
     int n;
     int kas = 1;
     while (cin>>n)
     {
         for (int i = 1,p,r;i <= n;++i)
         {
             scanf("%d%d",&p,&r);
             a[p] = r;
         }
         int len = 1;
         d[1] = a[1];
         for (int i = 2;i <= n;++i)
         {
             if (a[i] > d[len])
             {
                 d[++len] = a[i];
             }
             else
             {
                 int p = lower_bound(d,d+len,a[i]) - d;
                 d[p] = a[i];
             }
         }
         printf("Case %d:\n",kas++);
         if (len == 1) puts("My king, at most 1 road can be built.");
         else printf("My king, at most %d roads can be built.\n",len);
         puts("");
     }
     return 0;
 }