#include<iostream>
using namespace std;
int main(void)
{
	int i, j, k, ans = 0, hu = 0, n, m = 0, pa[105] = { 0 };
	char a[105][105][33], h[10] = "nyanpass";

	cin >> n;
	for (j = 1; j <= n; j++) {

		for (i = 1; i <= n; i++) {

			cin >> a[j][i];
			m = 0;
			for (k = 0; k < 9; k++) {
				if (a[j][i][k] == h[k])
					m++;
				else break;

				if (m == 9)	pa[i]++;
			}
		}
	}
	
	for (int min = n - 1;min>0; min--) {
		for (i = 1; i <= n; i++) {
			if (min == pa[i]) {
				ans = i;
				hu++;
			}
		}
		if (hu > 0)break;
	}

	if (hu != 1)ans = -1;

	cout << ans << endl;

	return 0;
}