def solve(s, i, j):
    res = 6
    if j == len(s):
        i += 1
        j = i + 1
    if i < len(s) - 1:
        if s[i][j] == '-':
            s[i][j] = 'x'
            s[j][i] = 'o'
            res = min(res, solve(s, i, j + 1))
            s[i][j] = 'o'
            s[j][i] = 'x'
            res = min(res, solve(s, i, j + 1))
            s[i][j] = '-'
            s[j][i] = '-'
        else:
            res = min(res, solve(s, i, j + 1))
    else:
        c = []
        for si in s:
            c.append(si.count('o'))
        cs = list(set(c))
        cs.sort(reverse=True)
        res = cs.index(c[0]) + 1
    return res

n = int(input())
s = []
for i in range(n):
    s.append(list(input()))

res = solve(s, 0, 1)
print(res)