Thread: Ways to speed up a bruteforce-style program

Originally Posted by quzah

Why don't you use any of the is functions? isalnum would give you any letter or digit, or isprint would tell you if it was a printable character. Most of those checks are going to be lookup tables anyway. isprint is going to give you pretty much every valid character that would be used, and should be a fast way to see if the resulting check's suggested encoding character was valid or not. It seems like your if check you use a lot could be replaced with:

Code:

//if((ch < 'A') || (ch>90 && ch<97)) {
if( isprint( ch ) ) // or isalnum .. if you're assuming no punctuation/whitespace to start

I'm also not sure about your rule where you can't be entering nonpunctuation. I guess because we're assuming that the encrypted text doesn't start a line with a period? Was that a stipulation by the OP?


Quzah.

That's right:

has been "encrypted" like this, using a five letter lowercase word.

I didn't want to limit my program to a lowercase password, though.

All these char's are printable. isprint() doesn't help, since it wouldn't exclude char's like '['. I did allow some such char's as possibles later on, but at first, I thought it would be too slow if I included them as possible char's in the search.

Originally Posted by quzah

[ is a printable character: man isprint


Quzah.

Sure, that's why isprint() wouldn't exclude it, and why I didn't use isprint(). Although I later allowed some non-word char's into the search for the password, I never allowed any char with a value above 'z'.

Originally Posted by Adak

Sure, that's why isprint() wouldn't exclude it, and why I didn't use isprint(). Although I later allowed some non-word char's into the search for the password, I never allowed any char with a value above 'z'.

or isalnum .. if you're assuming no punctuation/whitespace to start

Or even isalpha if you've got something against numbers.

That's the duality - on the one hand, I like the idea of a general substitution program, that would handle numbers, punctuation, and space(s).

On the other hand, that wasn't part of the OP's problem, and I did want to stay more or less, focused on that.

I'll put together something to test the better algorithm idea from my earlier post (#15). What do you think - should a program like this include numbers and char's like $#@%*=+, or not?

Awww! OK. Now I get what you meant. Merry Christmas, Quzah.