I spotted the type casting of int but I have not thought it constrained all the operations too

In C, when you say int q;, that variable is fixed to, depending on how your compiler defines it, a 32 (or 16 or 64) bit signed integer value, no more, no less - simplifying a bit, no matter what you try to assign to it, it will be cast back to an int.

Now I ported to a more perlish versions, but speaking frankly, I'm quite struggling with it's efficiency.

Since functionally the two programs are practically identical, that'll simply be the difference between a complied and interpreted language. I don't have much time for optimization right now, but you might try to compare the performance of the program with and without use integer; - I'm not sure if it'll make a significant difference but it's worth a try.

In reality I'm working blindly not have well understood wht the code do.

A bit of googling on the algorithm brings me to this page, while it's a bit difficult to read visually, it seems to give an example-based explanation of the "spigot algorithm" that this appears to be an implementation of.

In reply to Re^3: porting C code to Perl -- solved by haukex
in thread porting C code to Perl by Discipulus

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