import os, sys
from io import IOBase, BytesIO
py2 = round(0.5)
if py2:
    from future_builtins import ascii, filter, hex, map, oct, zip
    range = xrange
BUFSIZE = 8192
class FastIO(BytesIO):
    newlines = 0
 
    def __init__(self, file):
        self._file = file
        self._fd = file.fileno()
        self.writable = 'x' in file.mode or 'w' in file.mode
        self.write = super(FastIO, self).write if self.writable else None
 
    def _fill(self):
        s = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
        self.seek((self.tell(), self.seek(0,2), super(FastIO, self).write(s))[0])
        return s
 
    def read(self):
        while self._fill(): pass
        return super(FastIO,self).read()
 
    def readline(self):
        while self.newlines == 0:
            s = self._fill(); self.newlines = s.count(b'\n') + (not s)
        self.newlines -= 1
        return super(FastIO, self).readline()
 
    def flush(self):
        if self.writable:
            os.write(self._fd, self.getvalue())
            self.truncate(0), self.seek(0)
 
class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        if py2:
            self.write = self.buffer.write
            self.read = self.buffer.read
            self.readline = self.buffer.readline
        else:
            self.write = lambda s:self.buffer.write(s.encode('ascii'))
            self.read = lambda:self.buffer.read().decode('ascii')
            self.readline = lambda:self.buffer.readline().decode('ascii')
 
 
sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline().rstrip('\r\n')
 
# Cout implemented in Python
import sys
class ostream:
    def __lshift__(self,a):
        sys.stdout.write(str(a))
        return self
cout = ostream()
endl = '\n'

def get_input(a=str):
    return a(input())

def get_int_input():
    return get_input(int)

def get_input_arr(a):
    return list(map(a, input().split()))

def get_int_input_arr():
    return get_input_arr(int)





def solve():
    t = get_int_input()

    for _ in range(t):

        n = get_int_input()

        grid = []
        
        for i in range(n):
            grid.append(get_input())
        # print(grid)

        if grid[0][1] == grid[1][0] and grid[-2][-1] == grid[-1][-2] and grid[-1][-2] != grid[0][1]:
            cout<<0<<endl
        elif grid[0][1] == grid[1][0] and grid[-2][-1] == grid[-1][-2] and grid[-1][-2] == grid[0][1]:
            cout<<2<<endl
            cout<<1<<" "<<2<<endl
            cout<<2<<" "<<1<<endl
        elif grid[0][1] != grid[1][0] and grid[-2][-1] == grid[-1][-2]:
            if grid[1][0] == grid[-2][-1]:
                cout<<1<<endl
                cout<<2<<" "<<1<<endl
            elif grid[0][1] == grid[-2][-1]:
                cout<<1<<endl
                cout<<1<<" "<<2<<endl
        elif grid[0][1] == grid[1][0] and grid[-2][-1] != grid[-1][-2]:
            if grid[1][0] == grid[-2][-1]:
                cout<<1<<endl
                cout<<n - 1<<" "<<n<<endl
            elif grid[0][1] == grid[-1][-2]:
                cout<<1<<endl
                cout<<n<<" "<<n - 1<<endl
        elif grid[0][1] != grid[1][0] and grid[-2][-1] != grid[-1][-2]:
            if grid[0][1] == grid[-2][-1]:
                cout<<2<<endl
                cout<<1<<" "<<2<<endl
                cout<<n<<" "<<n - 1<<endl
            if grid[0][1] == grid[-1][-2]:
                cout<<2<<endl
                cout<<1<<" "<<2<<endl
                cout<<n - 1<<" "<<n<<endl
        





def main():
    solve()


if __name__ == "__main__":
    main()