You’d likely end up in an infinite do-loop. It’d just print out BUY IT, BUY IT, …In the early 80s, a traffic engineering firm[1] I worked for use a program called Transyt 7. It could analyze data for up to fifty signalized intersections in almost any arrangement and spit out suggestions for timing and coordinating the signals based on how you wanted to optimize flow.[2] Pretty complex. Our biggest run took 30 seconds on a CDC Cyber 74 (one of the better supercomputers at the time), 30 minutes on a DEC VAX 11/750 (a great minicomputer), and 30 hours on the just released IBM Personal Computer. I admit to being a bit underwhelmed with the PC (never mind that DOS 1.0 was a farce).
I'd love to know how quick that run would be on a Thunderbird, but I don't have a copy of the input data, or a FORTRAN compiler for a Thunderbird of any stripe.
[1][ JHK, once a part of Peat-Marwick, later bought by PRC Voorhees who was bought by someone else, IIRC
[2] One gets the impression most cities don't bother to run such programs.


