On 05/29/2012 07:33 PM, ixid wrote:
Having solved Project Euler 300 I wanted to explore which of the
strictly superior fold set were redundant but started getting an
exception thrown after a few iterations.
I've changed the offending part to try to make it as impact-free as
possible (my code is not pretty :)), it's now pure and the return is
only used with writeln to track the progress of the function yet it
still causes an exception after 4 or 5 iterations.
http://pastebin.com/j6REskhd
The offending function is 'solve', which I've repeatedly called to make
the exception as simple as possible along with const data and limited
use of the return data. I've tried making it pure/const as well as
adding delete on the main data and also removing pure and calling the
garbage collector. This is the stack trace crash assembler command:
7C90E8E5 push ebx
Does this mean there is a stack overflow? Any ideas what on earth is
going on?
I haven't even run your program but I think your guess is correct: You
are probably running out of stack space. The reason must be the fact
that you pass fixed-length arrays by value.
LEN being 15, especially 'bits' is a very large array:
pure int[] solve(const bool[] redundancy, const ushort[LEN - 1][]
matrixes, const int[2^^LEN] bits, const int[] numbers)
Fixed-length arrays are value types and are copied on the stack. Try
passing 'bits' as 'const ref' instead of just 'const'.
Ali
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