for _ in range(int(input())):
    n = int(input())
    g = [input() for _ in range(n)]

    x1 = g[0][1] + g[1][0]
    x2 = g[-1][-2] + g[-2][-1]

    if x1 == x2:
        print(2)
        print(1, 2)
        print(2, 1)
        continue

    if x1[0] != x2[0] and x1[1] != x2[1]:
        print(0)
        continue

    if x1[0] == x1[1] == x2[0]:
        print(1)
        print(n, n-1)
        continue

    if x1[0] == x1[1] == x2[1]:
        print(1)
        print(n-1, n)
        continue
