[QUOTE=SmartMersenne;560230]I really doubt that it will come anywhere close to July20.[/QUOTE]

I wish I could call you "pessimistic".
Looking at the past three years, Oct20 seems somehow similar to Nov17, another "find-constrained-algorithm" challenge. Nov17 was actually solved by 23 people only.
On the other hand, both Oct20 and July20 deal with linear-recurrenced sequences, candidate solutions can be analyzed with similar linear algebra methods.

About CHAOS, I found it useful to know that the following kind of instruction is permitted:
30 CHAOS 30, 40, 50, ...
so that the control flow graph has an edge from a one-line block to itself.

[QUOTE=0scar;560480]I wish I could call you "pessimistic".
Looking at the past three years, Oct20 seems somehow similar to Nov17, another "find-constrained-algorithm" challenge. Nov17 was actually solved by 23 people only.
On the other hand, both Oct20 and July20 deal with linear-recurrenced sequences, candidate solutions can be analyzed with similar linear algebra methods.

About CHAOS, I found it useful to know that the following kind of instruction is permitted:
30 CHAOS 30, 40, 50, ...
so that the control flow graph has an edge from a one-line block to itself.[/QUOTE]

But that isn't necessary! There are solutions for both problems (0,2,2,... and 1970) without using this trick.

[QUOTE=Dieter;560493]But that isn't necessary! There are solutions for both problems (0,2,2,... and 1970) without using this trick.[/QUOTE]

I agree at 100% with you.
Had it been necessary, writing it would have been too spoiling.
I only wrote that I found it useful (shorter code, faster reaching 1970)

[QUOTE=0scar;560515]I agree at 100% with you.
Had it been necessary, writing it would have been too spoiling.
I only wrote that I found it useful (shorter code, faster reaching 1970)[/QUOTE]

How fast? My fastest is 1970 = 10th value of the sequence, but I search no more.

[QUOTE=Dieter;560521]How fast? My fastest is 1970 = 10th value of the sequence, but I search no more.[/QUOTE]

The "trick" itself is just one more degree of freedom in writing code.
Of course I can remove all "tricky" edges from my solutions; the easiest way requires to keep the same number of incoming/outcoming edges by adding suitable nodes as new sources/destinations, which means some more CHAOS lines.
As an example, the length of my 7-step bonus solution grows from 17 to 19, not a problem, but I judge the "tricky" version more efficient.
So far, I found no "untricky" solutions which fit both the 6-step and the 20-line constraints.

I don't fully understand the second block of code within published base solution.
I suppose that new code lines must be inserted as follows:

[QUOTE]10 A = a
20 B = b
24 Z = 42
25 JMP_ZERO A 75
30 JMP_ZERO B 80
40 X = A % B
50 A = B
60 B = X
70 JMP 30
75 CHAOS 76, 77, 80
76 CHAOS 75, 77, 80
77 CHAOS 75, 76, 80
80 RETURN A[/QUOTE]

If a and b are non-negative integers with a >= b, it makes sense.

What about line 24?
I argue that Gadi's program also computes the Answer to Life, the Universe, and Everything.
But it won't be returned before seven and a half million years...

[QUOTE=0scar;562196]I don't fully understand the second block of code within published base solution.
I suppose that new code lines must be inserted as follows:



If a and b are non-negative integers with a >= b, it makes sense.

What about line 24?
I argue that Gadi's program also computes the Answer to Life, the Universe, and Everything.
But it won't be returned before seven and a half million years...[/QUOTE]

The question was stupid to start with. Our goal is to find better and efficient solutions everywhere but in this question, we are intentionally adding stupidity (chaos) to the solution.

[QUOTE=0scar;560480]I wish I could call you "pessimistic".
Looking at the past three years, Oct20 seems somehow similar to Nov17, another "find-constrained-algorithm" challenge. Nov17 was actually solved by 23 people only.
On the other hand, both Oct20 and July20 deal with linear-recurrenced sequences, candidate solutions can be analyzed with similar linear algebra methods.
[/QUOTE]

Yup, the number of solvers was barely able to reach 25, so clarification didn't have a special boost.

[QUOTE=SmartMersenne;562211]The question was stupid to start with. Our goal is to find better and efficient solutions everywhere but in this question, we are intentionally adding stupidity (chaos) to the solution.[/QUOTE]
[QUOTE=SmartMersenne;562215]Yup, the number of solvers was barely able to reach 25, so clarification didn't have a special boost.[/QUOTE]

As a joke, we could say that few people were stupid enough to solve the puzzle

[QUOTE=0scar;562196]I don't fully understand the second block of code within published base solution.
I suppose that new code lines must be inserted as follows:



If a and b are non-negative integers with a >= b, it makes sense.

What about line 24?
I argue that Gadi's program also computes the Answer to Life, the Universe, and Everything.
But it won't be returned before seven and a half million years...[/QUOTE]

Perhaps line 24 contains a hint for the november challenge...

[QUOTE=Dieter;562257]Perhaps line 24 contains a hint for the november challenge...[/QUOTE]

I still believe that variable "Z" stands for "Zaphod Beeblebrox" :-)