#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
int main(){
  int n;
  while(cin >>n,n){
    double x[100],y[100];
    int m = 1;
    for(int i=0; i<n; i++) scanf("%lf,%lf",&x[i],&y[i]);
    for(int i=0; i<n; i++){
      for(int j=i+1; j<n; j++){
	double dx,dy,dis,sq,s,t;
	int a;
	dx = x[i]-x[j];
	dy = y[i]-y[j];
	dis = dx*dx+dy*dy;
	if(dis<=4.0000001){
	  sq = sqrt(dis-dis*dis/4);
	  s = ((dis/2)*dx+dy*sq)/dis+x[j];t = ((dis/2)*dy-dx*sq)/dis+y[j];a = 0;
	  for(int k=0; k<n; k++) if((x[k]-s)*(x[k]-s)+(y[k]-t)*(y[k]-t)<=1.0000001) a++;
	  if(a>m) m = a;
	  s = ((dis/2)*dx-dy*sq)/dis+x[j];t = ((dis/2)*dy+dx*sq)/dis+y[j];a = 0;
	  for(int k=0; k<n; k++) if((x[k]-s)*(x[k]-s)+(y[k]-t)*(y[k]-t)<=1.0000001) a++;
	  if(a>m) m = a;
	}
      }
    }
    cout <<m<<endl;
  }
  return 0;
}