We're goin' Loopy

[Steven G]

With getting actual 5digit numbers (missed that!),
there are 30 solutions:
1: 13999
2: 19399
3: 19939
...
28: 99391
29: 99913
30: 99931

Now that you have 200 posts you have to go to the corner for 40 minutes for this mistake.

 

[Denis]

2*4*5 or 2*5*4 or......or 5*4*2 minutes?

 

[mmm4444bot]

With getting actual 5digit numbers (missed that!), there are 30 solutions …

My nested loopers gave me the numbered list last night, in less than one second. (But the coding took about three minutes; forgot Maple's weird closing delimiter 'od' -- had to look it up.)

Also, I had thought kolev02 was taking a beginning programming course (where "efficiency" doesn't matter).

I will, however, go to the corner for 2,187 seconds, as I mistakenly posted 'combinations' when I meant 'permutations'.

Edit: And, no, I'm not going to play Xs & Os with you, Denis.

 

[Denis]

Edit: And, no, I'm not going to play Xs & Os with you, Denis.

....ah c'mon...I'll let you go first....

Is your program along the lines of:

FOR a = 1 TO 9 STEP 2
...
FOR e = 1 TO 9 STEP 2

???

 

[mmm4444bot]

Yeah, but, nah. (I wasn't concerned about "efficiency".)

Instead of stepping through the odds, you could write a new looping subroutine (in machine language -- for extra efficiency) that starts with index 1, incrementing by a factor of 3, until the index reaches 9, whereupon the loop is closed.

And, thanks for reminding me; I need to delete my temp file.

[FONT=Courier New]> n:=0;
> for a from 1 to 9 do
>   for b from 1 to 9 do
>     for c from 1 to 9 do
>       for d from 1 to 9 do
>         for e from 1 to 9 do
>           if a*b*c*d*e=2187 then
>             n:=n+1;
>             print(a,b,c,d,e);
>           fi
>         od
>       od
>     od
>   od
> od;
> print(n);[/FONT]

That's right! I do not annotate my code, either. :cool: