#include <iostream>
#include <stdlib.h>

using namespace std;
int xy[700][2]={0};
int x[700]={0};
int best=0;
double currentk=0;
bool ok(int t)
{   
    double k=0;
    int i;
    for(i=t-1;i>0;i++)
     if(x[i]==1)break;
    if(i==0) return true;
    else
    { if(xy[t][0]=xy[i][0]) k=10000;
      else
      k=((double)(xy[t][1]-xy[i][1]))/((double)(xy[t][0]-xy[i][0]));
      if(currentk=0)currentk=k;
      else if(x[t]==1&&k==currentk)return true;
      else if(x[t]==0) return true;
      return false;
    }
          
}



void bt(int t,int n)
{
    if(t>n)
    { int s=0;
      for(int i=1;i<=n;i++)
      if(x[i]==1)s++;
      if(s>best)best=s;
      
    }
    
    else
        if(t==1){currentk=0;best=0;}
            for(int i=0;i<=1;i++)
            {  
                x[t]=i;
                if(ok(t))bt(t+1,n);
                x[t]=0;
            }
}                           
                            

int main(int argc, char *argv[])
{
    int m;
    while(cin>>m,m)
    { for(int i=1;i<=m;i++)
       cin>>xy[i][0]>>xy[i][1];
       bt(1,m);
       cout<<best<<endl;
       best=0;currentk=0;
   }       
  
                   
                                   
                                                                   
      
  system("PAUSE");	
  return 0;
}

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