import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

    // Complete the solve function below.
  
    public static void main(String[] args) throws IOException {
        int t,n,a=-1,b=-2,z=-9;
        boolean c=true;
        Scanner s=new Scanner(System.in);
        t=s.nextInt();
        for(int i=0;i<t;i++)
        {
            a=-1;
            b=-2;
            //System.out.println("hey");
            n=s.nextInt();
            
            
            for(int j=0;j<n;j++)
            {   a=s.nextInt();
                for(int k=0;k<n;k++)
                {
                    if(z==a)
                    c=false;
                    z=a;
                b=s.nextInt();
                if(a==b)
                    c=false; 
                }
                else{
                    a=b;
                    b=-2;
                }
            }
            if(c)
                System.out.println("Yes");
            else
                System.out.println("No");
        }
        
    }
}