class FlippingMatrix:

def __init__(self, n, matrix):

self.n = n

self.matrix = matrix

def max_sum_of_quadrant(self):

return sum(self.max_quadrant())

def max_quadrant(self):

return [max(self.upper_left_quadrant(row, col),

self.upper_right_quadrant(row, col),

self.lower_left_quadrant(row, col),

self.lower_right_quadrant(row, col))

for row in range(self.n)

for col in range(self.n)]

def upper_left_quadrant(self, row, col):

return self.matrix[row][col]

def upper_right_quadrant(self, row, col):

return self.matrix[row][self.flip(col)]

def lower_left_quadrant(self, row, col):

return self.matrix[self.flip(row)][col]

def lower_right_quadrant(self, row, col):

return self.matrix[self.flip(row)][self.flip(col)]

def flip(self, axis):

return 2 * self.n - 1 - axis

q = int(input().strip())

for _ in range(q):

n = int(input().strip())

matrix = []

for _ in range(2 * n):

matrix.append(list(map(int, input().strip().split(' '))))

print(FlippingMatrix(n, matrix).max_sum_of_quadrant())