Area of steel calculation in a beam cross section

I want to repeat certain steps in side a program in Mathcad. Is it possible?
For example in a beam cross section i will fill the bars in one layer until the spacing of the bars is not less then minimum spacing and then i will check if the design moment is less than or equal to resisting moment. If not i have to repeat certain steps and place the bars in more than one layers until the design moment is almost equal to resisting moment. 
I have a program to place the bars in one layer, how can i tell mathcad programming  to repeat these steps for the second and third layers?