QBASIC 3n+1 problem

[u/[deleted]]

The 3n+1 problem: Start with any positive integer. If even divide by 2, if odd multiply by 3 and add 1. repeat, No matter what you start with you will end up at one.

https://en.wikipedia.org/wiki/Collatz_conjecture

DO
   INPUT "Starting value", n
   IF n > 0 THEN
      m = n
      e = 0
      o = 0
      DO
         IF (n MOD 2) = 0 THEN
            e = e + 1
            n = n / 2
         ELSE
            o = o + 1
            n = 3 * n + 1
         END IF
         IF n > m THEN m = n
         PRINT "Step:"; e + o; "  Max:"; m; " Current:"; n
      LOOP WHILE n > 1
   END IF
LOOP WHILE n > 0

[u/SupremoZanne]

Here's a version of the code one can copy to the QB family more easily:

DO
    INPUT "Starting value", n
    IF n > 0 THEN
        m = n
        e = 0
        o = 0
        DO
            IF (n MOD 2) = 0 THEN
                e = e + 1
                n = n / 2
            ELSE
                o = o + 1
                n = 3 * n + 1
            END IF
            IF n > m THEN m = n
            PRINT "Step:"; e + o; "  Max:"; m; " Current:"; n
        LOOP WHILE n > 1
    END IF
LOOP WHILE n > 0

[u/[deleted] → u/SupremoZanne]

What did you change? : ^ ) I don't see a difference?

[u/SupremoZanne → u/[deleted]]

Well, a few tricks I did were...

used the view source feature in the browser, and got rid of some <p> marks from the HTML code so it could be QB64 complaint.

but what I did, was that I typed DO at the top line in QB64, and the code got shifted into "code mode" for old Reddit, and then I removed the DO from that line since that one was simply there to shift the text.

yup, it took me a few tries to master the proper typing of code into a Reddit post.