small prog.writing with S7-300 plc

I want to make a small prog.with S7-300.There is an elevator.Upstroke output is a Q4.0 and downstroke is Q5.0.Normally elevator is up and down one time.But if I want two times up and down move for elevator ( I will use a selector key for this )How can I success very simply?Thanks is advance..

Old prog.is;

A M3.3
=Q4.0 // Elevator is upstroke

A M3.3
A I2.7 // Limit switch spiral carriage up
S M3.4
R M3.3

A M3.4
=Q5.0 // Elevator is downstroke

Response

the simplest way, in my opinion, is to create a loop for the program displayed above, at the end of the program you select a variable V that is incremented any time the program in the loop is executed. In the front of this you put an equal comparation: V and 2, if =, then the loop is stopped, else run the loop.
in extension, for a given number of repeats you modify only the input of comparator.

Thanks a lot for response.I solved problem.I used a down counter for this.the M3.3 set counter with value 2. When the elevator go down than count is decrease one .Until the counter is zero elevator will go up and down.When the counter is equal to zero than program skips to next step.