beginning_of_program
define_new_instruction turnright as
iterate 3 times
turnleft;
define_new_instruction mover as
{if front_is_clear then {move;}
else
busca_puerta;}
define_new_instruction zig_zag as
{if front_is_clear then
{turnleft; 
mover;
turnright;}
{if front_is_clear then
mover;}
{if front_is_clear then
{turnright; 
mover; 
turnleft; 
mover;
zig_zag;}}
else turnleft;
define_new_instruction busca_puerta as
{if right_is_clear then
{turnright; move;
busca_puerta;}
else
{if front_is_clear then
{move; busca_puerta;}
else
{turnleft; busca_puerta;}}}

beginning_of_execution
busca_puerta;

busca_puerta;

turnoff;

end_of_execution
end_of_program