#include <vector>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <algorithm>
#include <utility>
#include <functional>
#include <sstream>
#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <climits>
#include <fstream>
using namespace std;
inline int toInt(string s) { int v; istringstream sin(s); sin >> v; return v;}
template<class T> inline string toStr(T x) { ostringstream sout; sout << x; return sout.str();}
typedef vector<int> vi;
typedef vector<vi>  vvi;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef long long ll;
#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define FOR(i,a,b) for(int i=(a);i<=(b);++i)
#define REP(i,n) FOR(i,0,(n)-1)
const double EPS = 1e-12;
const double PI = acos(-1.0);
const int INF = INT_MAX/10;

#include <complex>
typedef complex<double> P;
typedef vector<P> vp;

#define LT(x,y) ((x)-(y)<=-EPS)

P center(P a, P b) {
	return P((a.real()+b.real())/2, (a.imag()+b.imag())/2);
}

int main() {
	int n;
	while(cin >> n, n) {
		vp points(n);
		double x, y;
		char c;
		REP(i, n) {
			cin >> x >> c >> y;
			points[i] = P(x, y);
		}

		vector<vp> cpoints(n, vp(n));
		REP(i, n) {
			REP(j, n) {
				cpoints[i][j] = center(points[i], points[j]);
			}
		}

		int ans = 0;
		REP(i, n) {
			REP(j, n) {
				int tmp = 0;
				REP(k, n) {
					if(LT(abs(cpoints[i][j]-points[k]),1.0)) {
						tmp++;
					}
				}
				ans = max(ans, tmp);
			}
		}

		cout << ans << endl;
	}
	return 0;
}