import os
import sys
from io import BytesIO, IOBase

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")
##########################################################
import math
import bisect

from collections import Counter
# sys.setrecursionlimit(10**6)
# dp=[[-1 for i in range(n+5)]for j in range(cap+5)]
# arr= list(map(int, input().split()))
# n,m= map(int, input().split())
# arr= list(map(int, input().split()))
# for _ in range(int(input())):
import bisect
# n=int(input())
#for _ in range(int(input())):
import heapq as h
#n=int(input())
from collections import defaultdict
#n,m=map(int, input().split())
#ls= list(map(int, input().split()))
# Python3 program to count inversions using
from collections import deque




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

    n=int(input())
    g=[]

    for i in range(n):
        s=list(input())
        g.append(s)
    if g[0][1]==g[1][0] and g[0][1]=="0":

        ans=[]
        if g[n-1][-2]=="0":
            ans.append([n,n-1])
        if g[n-2][n-1]=="0":
            ans.append([n-1,n])
        print(len(ans))
        for k in ans:
            print(*k)
    elif g[0][1]==g[1][0] and g[0][1]=="1":

        ans=[]
        if g[n-1][-2]=="1":
            ans.append([n,n-1])
        if g[n-2][n-1]=="1":
            ans.append([n-1,n])
        print(len(ans))
        for k in ans:
            print(*k)


    else:
        
        if g[n-1][n-2]==g[n-2][n-1]=="0":
            ans=[]
            if g[0][1]!= "1":
                ans.append([1,2])
            if g[1][0]!="1":
                ans.append([2,1])
            print(len(ans))
            for k in ans:
                print(*k)
        elif g[n-1][n-2]==g[n-2][n-1]=="1":
            ans=[]
            if g[0][1]!= "0":
                ans.append([1,2])
            if g[1][0]!="0":
                ans.append([2,1])
            print(len(ans))
            for k in ans:
                print(*k)
        else:
            ans=[]
            if g[0][1]!= "1":
                ans.append([1,2])
            if g[1][0]!="1":
                ans.append([2,1])
            if g[n-1][n-2]!="0":
                ans.append([n,n-1])
            if g[n-2][n-1]!="0":
                ans.append([n-1,n])
            print(len(ans))
            for k in ans:
                print(*k)
  