#!/usr/bin/env python
import os
import sys
from io import BytesIO, IOBase
import threading 
from bisect import bisect_right
from math import gcd,log
from collections import Counter
from pprint import pprint
from itertools import combinations 

def fun(val,grid,n):
    # print(grid)
    bfs=[(0,0)]
    delta=[(1,0),(-1,0),(0,1),(0,-1)]
    visited=[[0]*n for i in range(n)]
    visited[0][0]=1
    while len(bfs):
        # print(bfs,val)
        x,y=bfs.pop()
        if x==y==n-1:
            return True
        for dx,dy in delta :
            nx=x+dx
            ny=y+dy
            if 0<=nx<n and 0<=ny<n and visited[nx][ny]==0 and grid[nx][ny] in [val,'F']:
                visited[nx][ny]=1
                bfs.append((nx,ny))
    return False




def main():
    n=int(input())
    arr=[]
    for i in range(n):
        arr.append([c for c in input()])
    l=[(1,0),(0,1),(n-1,n-2),(n-2,n-1)]
    c=list(combinations(l,0))+list(combinations(l,1))+list(combinations(l,2))

    for li in c :
        # print(li)
        for x,y in li :
            arr[x][y]='1' if arr[x][y]=='0' else '0'

        if fun('0',arr,n) or fun('1',arr,n):
            pass
        else:
            print(len(li))
            for x,y in li :
                print(x+1,y+1)
            return 
        for x,y in li :
            arr[x][y]='1' if arr[x][y]=='0' else '0'

    




    


    
        
BUFSIZE = 8192
 
 
class FastIO(IOBase):
    newlines = 0
 
    def __init__(self, file):
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = "x" in file.mode or "r" not in file.mode
        self.write = self.buffer.write if self.writable else None
 
    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()
 
    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.newlines = b.count(b"\n") + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()
 
    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)
 
 
class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        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")
 
# endregion
 
if __name__ == "__main__":

    for _ in range(int(input())):
        main()



