GP Beta Test Forum

yes, i did, using myZip, myZipWidth and a couple of helper functions. and it validated 1234567812345670 and 49927398716 (fake numbers, of course) as good credit card numbers. i hesitate to upload the program because the problem is a perfect exercise for programmers learning a new language. taking 49...

thanks for the advice - it's much simpler now. here's the updated source:

i built a 'when space pressed, STOP' block but it doesnt seem to work - either in the development mode or even the exported app. it seems to act like a no-operation or short pause. replacing it with HALT, will work, though. im running this in windows 10. is there something i'm missing?

when i learned about GP, i immediately tried to use it to encode the luhn algorithm that checks for good credit card numbers- but soon learned that GP did not have a zipWith function! so i wrote my own version. ( in haskell, zipWith (*) [2,3,4] [5,4,6] would return a list of [10,12,24].) zipwith cop...

i did it too - to practice coding in gp blocks . it was fun! i got the right answer using all the info supplied. while i was there i also solved the easy (to me!) ones: multiples of 3 and 5 https://projecteuler.net/problem=1 , sum square difference https://projecteuler.net/problem=6 and number lette...

i would use it to "comment out" intermediate debugging code, for example.
it can also serve as a garbage bag for sticking unused objects floating in workspace because they were dislodged, or they were trying out temporary code, etc, then when you've collected enough, just drag it out to delete.

i've proven that reduce can perform sum as shown below but i cannot get this reduce to reverse the list isn't reduce the equivalent of haskell's foldl?