import javax.security.auth.login.AccountNotFoundException;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.CookieHandler;
import java.util.*;
/*

Just Practice bro
 */
//--------------------------------------------------------------------------------------------------------------------------------------------------------------

public class Main {
    public static void main(String[] args) {
//        Scanner sc = new Scanner(System.in);
        FastScanner sc = new FastScanner();
        PrintWriter out = new PrintWriter(System.out);
        int t=sc.nextInt();
        while (t-->=1){
           int n=sc.nextInt();
           char ch[][]= new char[n][n];
           for (int i=0;i<n;i++){
               String s=sc.next();
               for (int j=0;j<n;j++){
                   ch[i][j]=s.charAt(j);
               }
           }
           int count1=0;
           int count2=0;
           if (ch[0][1]==ch[n-2][n-1]){
               count1++;
               if (ch[0][1]=='1')
               ch[n-2][n-1]='0';
               else if (ch[0][1]=='0'){
                   ch[n-2][n-1]='1';
               }
           }
            if (ch[1][0]==ch[n-1][n-2]){
                count2++;
                if (ch[1][0]=='1')
                    ch[n-1][n-2]='0';
                else if (ch[1][0]=='0'){
                    ch[n-1][n-2]='1';
                }
            }
             if (count2==1&&count1==1){
                System.out.println(2);
                System.out.println((n-1)+" "+n);
                System.out.println((n)+" "+(n-1));
            }
            else if (count1==1&&count2==0){
                System.out.println(1);
                System.out.println((n-1)+" "+n);
            }
             else if (count2==1&&count1==0){
                System.out.println(1);
                System.out.println((n)+" "+(n-1));
            }

            else{
                System.out.println(0);
            }
        }

        out.flush();
    }
    //-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
    static void sort(int[] a) {
        ArrayList<Integer> l=new ArrayList<>();
        for (int i:a) l.add(i);
        Collections.sort(l);
        for (int i=0; i<a.length; i++) a[i]=l.get(i);
    }
    static int mod=(int)1e9+7;
    static long mod(long x){
        return ((x%mod+mod)%mod);
    }
    static long add(long x,long y){
        return mod(mod(x)+mod(y));
    }
    static long mul(long x,long y){
        return mod(mod(x)*mod(y));
    }
    static int[] find(int n,int start,int diff){
        int a[]= new int[n];
        a[0]=start;
        for (int i=1;i<n;i++)a[i]=a[i-1]+diff;
        return a;
    }
    static void swap(int a,int b){
        int c=a;
        a=b;
        b=c;
    }

    static void printArray(int a[]){
        for (int i=0;i<a.length;i++){
            System.out.print(a[i]+" ");
        }
    }
    static boolean sorted(int a[]){
        int n=a.length;
        boolean flag=true;
        for (int i=0;i<n-1;i++){
            if (a[i]>a[i+1])flag=false;
        }
        if (flag)return true;
        else  return false;
    }
    public static int findlog(long n){
        if(n == 0)
            return 0;

        if(n == 1)
            return 0;
        if(n == 2)
            return 1;
        double num = Math.log(n);
        double den = Math.log(2);
        if(den == 0)
            return 0;
        return (int)(num/den);
    }
    public static long gcd(long a,long b){
        if(b%a == 0)
            return a;
        return gcd(b%a,a);
    }
    public static int gcdInt(int a,int b){

        if(b%a == 0)
            return a;

        return gcdInt(b%a,a);

    }

    static void sortReverse(long[] a) {
        ArrayList<Long> l=new ArrayList<>();
        for (long i:a) l.add(i);
//        Collections.sort.(l);
        Collections.sort(l,Collections.reverseOrder());
        for (int i=0; i<a.length; i++) a[i]=l.get(i);
    }

    static class FastScanner {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st=new StringTokenizer("");
        String next() {
            while (!st.hasMoreTokens())
                try {
                    st=new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }
        int[] readArray(int n) {
            int[] a=new int[n];
            for (int i=0; i<n; i++) a[i]=nextInt();
            return a;
        }
        long[] readArrayLong(long n) {
            long[] a=new long[(int)n];
            for (int i=0; i<n; i++) a[i]=nextLong();
            return a;
        }
        long nextLong() {
            return Long.parseLong(next());
        }
    }


}