package main

import (
	"bufio"
	"fmt"
	"os"
	"sort"
	"strconv"
)

func recv(matrix [][]byte) int {

	for i := 0; i < len(matrix); i++ {
		for j := 0; j < len(matrix); j++ {
			if matrix[i][j] == '-' {
				matrix[i][j] = 'o'
				matrix[j][i] = 'x'
				A := recv(matrix)
				matrix[i][j] = 'x'
				matrix[j][i] = 'o'
				B := recv(matrix)
				matrix[i][j] = '-'
				matrix[j][i] = '-'
				return min(A, B)
			}
		}
	}

	var Q []int

	count := 0
	for j := 0; j < len(matrix); j++ {
		if matrix[0][j] == 'o' {
			count++
		}
	}
	Q = append(Q, count)
	for i := 1; i < len(matrix); i++ {
		cnt := 0
		for j := 0; j < len(matrix); j++ {
			if matrix[i][j] == 'o' {
				cnt++
			}
		}
		Q = append(Q, cnt)
	}

	sort.Ints(Q)
	reverse(Q, 0, len(Q))
	Q = unique(Q)

	for i, v := range Q {
		if v == count {
			return i + 1
		}
	}
	panic("")

}
func reverse(a []int, start int, length int) {
	var end = start + length - 1
	for start < end {
		a[start], a[end] = a[end], a[start]
		start++
		end--
	}
}

func unique(A []int) []int {
	mp := map[int]struct{}{}
	L := make([]int, 0, len(A))
	for _, v := range A {
		if _, ok := mp[v]; !ok {
			L = append(L, v)
			mp[v] = struct{}{}
		}
	}
	return L
}

func min(a int, b int) int {
	if a < b {
		return a
	}
	return b
}

func main() {
	sc := NewScanner()
	N := sc.NextInt()

	matrix := make([][]byte, N)
	for i := 0; i < N; i++ {
		matrix[i] = []byte(sc.NextLine())
	}
	fmt.Println(recv(matrix))

}

type Scanner struct {
	r   *bufio.Reader
	buf []byte
	p   int
}

func NewScanner() *Scanner {
	rdr := bufio.NewReaderSize(os.Stdin, 1000)
	return &Scanner{r: rdr}
}
func (s *Scanner) Next() string {
	s.pre()
	start := s.p
	for ; s.p < len(s.buf); s.p++ {
		if s.buf[s.p] == ' ' {
			break
		}
	}
	result := string(s.buf[start:s.p])
	s.p++
	return result
}
func (s *Scanner) NextLine() string {
	s.pre()
	start := s.p
	s.p = len(s.buf)
	return string(s.buf[start:])
}
func (s *Scanner) NextInt() int {
	v, _ := strconv.Atoi(s.Next())
	return v
}
func (s *Scanner) NextInt64() int64 {
	v, _ := strconv.ParseInt(s.Next(), 10, 64)
	return v
}

func (s *Scanner) NextIntArray() []int {
	s.pre()
	start := s.p
	result := []int{}
	for ; s.p < len(s.buf)+1; s.p++ {
		if s.p == len(s.buf) || s.buf[s.p] == ' ' {
			v, _ := strconv.ParseInt(string(s.buf[start:s.p]), 10, 0)
			result = append(result, int(v))
			start = s.p + 1
		}
	}

	return result
}
func (s *Scanner) NextInt64Array() []int64 {
	s.pre()
	start := s.p
	result := []int64{}
	for ; s.p < len(s.buf)+1; s.p++ {
		if s.p == len(s.buf) || s.buf[s.p] == ' ' {
			v, _ := strconv.ParseInt(string(s.buf[start:s.p]), 10, 64)
			result = append(result, v)
			start = s.p + 1
		}
	}
	return result
}

func (s *Scanner) NextMap() map[int]bool {
	s.pre()
	start := s.p
	mp := map[int]bool{}
	for ; s.p < len(s.buf); s.p++ {
		if s.buf[s.p] == ' ' {
			v, _ := strconv.Atoi(string(s.buf[start:s.p]))
			mp[v] = true
			start = s.p + 1
		}
	}
	v, _ := strconv.Atoi(string(s.buf[start:s.p]))
	mp[v] = true

	return mp
}

func (s *Scanner) pre() {
	if s.p >= len(s.buf) {
		s.readLine()
		s.p = 0
	}
}
func (s *Scanner) readLine() {
	s.buf = make([]byte, 0)
	for {
		l, p, e := s.r.ReadLine()
		if e != nil {
			panic(e)
		}
		s.buf = append(s.buf, l...)
		if !p {
			break
		}
	}
}