import java.util.Arrays; import java.util.Scanner; public class Main_origin { MyScanner sc = new MyScanner(); Scanner sc2 = new Scanner(System.in); long start = System.currentTimeMillis(); long fin = System.currentTimeMillis(); final int MOD = 1000000007; int[] dx = { 1, 0, 0, -1 }; int[] dy = { 0, 1, -1, 0 }; void run() { int n = sc.nextInt(); String[][] s = new String[n][4]; for (int i = 0; i < n; i++) { for (int j = 0; j < n; j++) { s[i][j] = sc.next(); } } int ans = -1; for (int i = 0; i < n; i++) { boolean all = true; for (int j = 0; j < n; j++) { if (!s[j][i].equals("-")) { if (!s[j][i].equals("nyanpass")) { all = false; } } } if (all) { if (ans == -1) { ans = i + 1; } else { System.out.println(-1); return; } } } System.out.println(ans); } public static void main(String[] args) { new Main_origin().run(); } void debug(Object... o) { System.out.println(Arrays.deepToString(o)); } void debug2(int[][] array) { for (int i = 0; i < array.length; i++) { for (int j = 0; j < array[i].length; j++) { System.out.print(array[i][j]); } System.out.println(); } } boolean inner(int h, int w, int limH, int limW) { return 0 <= h && h < limH && 0 <= w && w < limW; } void swap(int[] x, int a, int b) { int tmp = x[a]; x[a] = x[b]; x[b] = tmp; } // find minimum i (a[i] >= border) int lower_bound(int a[], int border) { int l = -1; int r = a.length; while (r - l > 1) { int mid = (l + r) / 2; if (border <= a[mid]) { r = mid; } else { l = mid; } } // r = l + 1 return r; } boolean palindrome(String s) { for (int i = 0; i < s.length() / 2; i++) { if (s.charAt(i) != s.charAt(s.length() - 1 - i)) { return false; } } return true; } class MyScanner { int nextInt() { try { int c = System.in.read(); while (c != '-' && (c < '0' || '9' < c)) c = System.in.read(); if (c == '-') return -nextInt(); int res = 0; do { res *= 10; res += c - '0'; c = System.in.read(); } while ('0' <= c && c <= '9'); return res; } catch (Exception e) { return -1; } } double nextDouble() { return Double.parseDouble(next()); } long nextLong() { return Long.parseLong(next()); } String next() { try { StringBuilder res = new StringBuilder(""); int c = System.in.read(); while (Character.isWhitespace(c)) c = System.in.read(); do { res.append((char) c); } while (!Character.isWhitespace(c = System.in.read())); return res.toString(); } catch (Exception e) { return null; } } int[] nextIntArray(int n) { int[] in = new int[n]; for (int i = 0; i < n; i++) { in[i] = nextInt(); } return in; } int[][] nextInt2dArray(int n, int m) { int[][] in = new int[n][m]; for (int i = 0; i < n; i++) { in[i] = nextIntArray(m); } return in; } double[] nextDoubleArray(int n) { double[] in = new double[n]; for (int i = 0; i < n; i++) { in[i] = nextDouble(); } return in; } long[] nextLongArray(int n) { long[] in = new long[n]; for (int i = 0; i < n; i++) { in[i] = nextLong(); } return in; } char[][] nextCharField(int n, int m) { char[][] in = new char[n][m]; for (int i = 0; i < n; i++) { String s = sc.next(); for (int j = 0; j < m; j++) { in[i][j] = s.charAt(j); } } return in; } } }