public string ProcessInput(List <string> input)
{
//token1 is in format of {Max_X Max_Y}
var token1 = input[0].Split(' ');
var lastValidPosition = new SurfaceCordinate(int.Parse(token1[0]), int.Parse(token1[1]));
//token2 is in format of {current_x current_y direction}
var token2 = input[1].Split(' ');
var currentPosition = new SurfaceCordinate(int.Parse(token2[0]), int.Parse(token2[1]));
var direction = new Direction(token2[2]);
var map = new Map(currentPosition, lastValidPosition);
//token3 is a string of instruction
//e.g. LLFFLL
var token3 = input[2];
var rover = new Rover(map, direction);
return(rover.ExecuteInstruction(token3));
}