> #include<iostream>
> #include<algorithm>
> using namespace std;
> struct fan
> {
> 	int a;
> 	int lon;
> 	int wth;
> 	int sum;
> }num[6000];
> bool op( struct fan x , struct fan y)
> {
> 	return x.sum < y.sum;
> };
> bool oop(struct fan xx, struct fan yy)
> {
> 	return xx.lon < yy.lon;
> };
> int main()
> {
> 	int lenth;
> 	int weight;
>     int s,t;
> 	int k = 0;
> 	while( cin >>s >> t && s != -1 && t != -1)
> 	{
> 		  if( s != 0 && t != 0)
> 		  { 
> 			  num[k].lon = s;
> 		      num[k].wth = t;
> 		      num[k].sum = s + t;
> 		      num[k].a = 1;
> 		      k++;
> 		  }
> 		  if( s == 0 && t == 0)
> 		  {
> 			   int count = 0;		
> 		       sort( num , num + k , op);
>                sort( num , num + k , oop);
> 		       int j,l;
> 		       for( j = 0 ; j < k ; j++)
> 				  {
> 					  if( num[j].a != 0)
> 					  {
> 						  count++;
> 						  lenth = num[j].lon;
> 						  weight = num[j].wth;
> 						  for( l = j + 1 ; l < k ; l++)
> 						   {                      
> 								  if( num[l].a != 0)
> 								  {
> 										  if( num[l].lon >= lenth )
> 										  {
> 													if( num[l].wth >= weight)
> 													{
> 														num[l].a = 0;
> 														lenth = num[l].lon;
> 														weight = num[l].wth;
> 		        									}
> 										  }							
> 								   }
> 							}
> 					   }
> 				   }
> 					 cout << count <<endl;
> 					 int rt ;
> 					 for( rt = 0 ; rt < k ; rt ++)
> 						 {
> 							  num[rt].a = 0;
> 							  num[rt].lon = 0;
> 							  num[rt].wth = 0;
> 				          }
> 					 k = 0;
> 		    }	
> 	}	
> 	system("pause");
> return 0;
> }