hdu5125 树状数组+dp

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <string.h>
using namespace std;
const int maxn=1005;
int a[maxn],b[maxn];
int c[maxn][maxn*2],h[maxn*2],L;
int lowbit(int x){
 return x&(-x);
}
void add(int loc, int floor,int v){
      while(loc<=L){
         c[floor][loc]=max(v,c[floor][loc]);
         loc+=lowbit(loc);
      }
}
int sum(int loc, int floor){
     int ans=0;
     while(loc>0){
         ans=max(c[floor][loc],ans);
         loc-=lowbit(loc);
     }
     return ans;
}

int main()
{
    int cas;
    scanf("%d",&cas);
    while(cas--){
         int n,m;
         scanf("%d%d",&n,&m);
         L=0;
         for(int i=0; i<n; ++i){
            scanf("%d%d",&a[i],&b[i]);
            h[L++]=a[i]; h[L++]=b[i];
         }
         memset(c,0,sizeof(c));
         sort(h,h+L);
         L=unique(h,h+L)-h;
         int ans=1;
         for(int i=0; i<n; ++i){
            int loca = lower_bound(h,h+L,a[i])-h+1;
            int locb = lower_bound(h,h+L,b[i])-h+1;
            int val;
            for(int j=min(i+1,m);j>0; j--){
                   val = sum(loca-1,j);
                   ans=max(ans,val+1);
                  add(loca,j,val+1);
                    val = sum(locb-1,j-1);
                   ans=max(ans,val+1);
                add(locb,j,val+1);
            }
                 val = sum(loca-1,0);
                 ans=max(ans,val+1);
                add(loca,0,val+1);
         }
         printf("%d\n",ans);
    }
    return 0;
}