HDU 1667 Nested Dolls

#include<iostream>
#include<algorithm>
#include<cstdio>
using namespace std;
class Node
{
public:
     int h,w;    
};
bool cmp( Node a ,Node b )
{
   if( a.w  == b.w )
      return a.h > b.h;
   return a.w < b.w;    
}
Node doll[20024];
int Doll( int n )
{
  int sum=0;
  int hash[20024]={0};
  for( int i = 0; i< n ; i++ )
  {
       int l = 0 ,r = sum;
       while( l < r )
       {
           int k = ( l + r )>>1;
           if( hash[k]>=doll[i].h )
               l = k + 1;
           else r = k;         
       }        
       hash[l] = doll[i].h;
       if( l == sum ) sum++;
  }
  return sum;    
}
int main( )
{
    int n,m;
    while( scanf( "%d",&n )==1 )
    {
       for( int i = 0; i< n ; i++ )
       {
           scanf( "%d",&m );
           for( int j = 0 ; j< m ; j++ )
            scanf( "%d%d",&doll[j].w, &doll[j].h );
           sort( doll , doll + m ,cmp );
           printf( "%d
",Doll( m ) );
       }    
    }
    return 0;    
}