for(%steps = 1; %a <= 100; %a++)
for(%current = %steps; %current <= 100; %current += %steps)
%door[%current] = !%door[%current];
for(%a = 1; %a <= 100; %a++)
echo("Door #" @ %a @ " is" SPC %door[%current] ? "Open" : "Closed" @ ".");