c# console move string_c# params

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.ForegroundColor = ConsoleColor.Yellow;
            int m = 0;
            int n = 0;
            Console.Write("zxl");
            do
            {
                switch (Console.ReadKey(true).Key)
                {
                    case ConsoleKey.UpArrow:
                        n = n - 1;
                        break;
                    case ConsoleKey.DownArrow:
                        n = n + 1;
                        break;
                    case ConsoleKey.LeftArrow:
                        m = m - 1;
                        break;
                    case ConsoleKey.RightArrow:
                        m = m + 1;
                        break;
                }
                Console.Clear();
                string aa = "";
                string bb = "";
                for (int a = 0; a < m; a++)
                {
                    aa += " ";
                }
                for (int b = 0; b < n; b++)
                {
                    bb += "\n";
                }
                Console.Write(bb + aa + "zxl");
            }
            while (true);
        }
    }
}