Code that got me through Level 11 and 12 of Untrusted

gistfile1.js

var player = map.getPlayer();
                
if (this.init === undefined) {
	this.player_last_x = player.getX();
	this.player_last_y = player.getY();
	this.init = true;
	return;
} 
if (player.getX() > this.player_last_x) me.move('right');
if (player.getX() < this.player_last_x) me.move('left');
if (player.getY() > this.player_last_y) me.move('down');
if (player.getY() < this.player_last_y) me.move('up');                    
                    
this.player_last_x = player.getX();
this.player_last_y = player.getY();