%union{
  struct {
	int x;
	int y;
  } loc;
  struct {
	int dx;
	int dy;
  } offset;
}
%token BEGIN_T EAST_T WEST_T NORTH_T SOUTH_T
%type <offset> instr
%type <loc> seq
%%
robot	:	seq		{printf("Robot is at (%d,%d)\n",$1.x,$1.y);}
	;

seq	:	seq instr	{$$.x=$1.x+$2.dx; $$.y=$1.y+$2.dy;}
	|	BEGIN_T		{$$.x=0;$$.y=0;}
	;

instr	:	EAST_T		{$$.dx=1; $$.dy=0;}
	|	WEST_T		{$$.dx=-1; $$.dy=0;}
	|	SOUTH_T		{$$.dx=0; $$.dy=-1;}
	|	NORTH_T		{$$.dx=0; $$.dy=1;}
	;
%%