"class SnowFlake:
    def __init__(self, side):
        self.side = side
        self.matrix = [['-' for i in range(side)] for j in range(side)]
        self.center = side // 2

    def freeze(self, n):
        self.side += n * 2
        new_matrix = [['-' for i in range(self.side)] for j in range(self.side)]

        for i in range(self.side):
            for j in range(self.side):
                if (i == self.center or j == self.center
                        or i - j == self.center or j - i == self.center
                        or i + j == self.center + self.side - 1
                        or i + j == self.center - self.side + 1):
                    ix[i][j] = ''

        self.matrix = new_matrix

    def thaw(self, steps):
        for i in range(steps):
            for j in range(self.center - i, self.center + i + 1):
                self.matrix[self.center - i][j] = '-'
                self.matrix[self.center + i][j] = '-'
                self.matrix[j][self.center - i] = '-'
                self.matrix[j][self.center + i] = '-'

    def thicken(self):
        for i in range(self.side):
            for j in range(1, self.center):
                if (self.matrix[i][j] == "" and
                        self.matrix[i][j - 1] == '-' and
                        self.matrix[i][self.side - j] == '-'):
                            self.matrix[i][j - 1] = ''
                            self.matrix[i][self.side - j] = ''

        for j in range(1, self.center):
            if (self.matrix[j][i] == '' and
                    self.matrix[j - 1][i] == '-' and
                    self.matrix[self.side - j][i] == '-'):
                self.matrix[j - 1][i] = ''
        self.matrix[self.side - j][i] = '*'

    def show(self):
        for row in self.matrix:
            print(' '.join(row))


zxc = SnowFlake(9)
zxc.thaw(10)"