Re^2: Happy 2006 (Golf)

Some golfing nitpicks:

Instead of int(rand 2)?'':'-', you can write '-'x rand 2, saving seven characters.
No need to quote 987654321, Perl will happely turn this integer into a string for you. This saves two characters.
Use $` instead of pos(). Three characters.
If you use an empty pattern in the substitution, Perl will do the right thing. Another five characters.
Use s### instead of s[][] for one character savings.

Result:

$ perl -e'($_=987654321)=~s##$`?(qw[+ - * /],("")x4)[rand 8]:"-"x rand
+ 2#ge while 2006!=eval;print'
9+8*7+654*3-21
[download]

Perl --((8:>*

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Re^3: Happy 2006 (Golf) by BrowserUk (Patriarch) on Jan 11, 2006 at 10:31 UTC
I'll go along with most of that except If you use an empty pattern in the substitution, Perl will do the right thing. Another five characters. Without the negative lookahead, the regex will produce a very high proportion of invalid expressions because it will insert an operator at the very end of the string: `9+87654/3-2/1- -9-8-76+5/43/2+1 987+6/54321 98/7-6+5-4/321+ 98/7/6/54-3/2-1 9/876543/21 -98/765432-1- -987/65-432+1* 98+7+654321- 9876/543+21 9876-54321* 987/6-5-4/3-21/ 9-8+765432+1 98765+4321+ -98-765432-1+ 9+87654321 9-87654-3-21 -987654-321+ 9876/54321- -9-876/5-4321 -987654+321 9/87+654321 98-7654/3+21 -987-6-54321 98+7+6/5+43+2-1 -98+76+543/2+1/ 9876543/21 -9-8+76-54321*` [download] Not always, and so it can be expected to still produce occasional correct answers, but it will take much longer and somehow offends my sensibilities :) Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal? "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]

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Re^3: Happy 2006 (Golf)
by BrowserUk (Patriarch) on Jan 11, 2006 at 10:31 UTC

I'll go along with most of that except

If you use an empty pattern in the substitution, Perl will do the right thing. Another five characters.

Without the negative lookahead, the regex will produce a very high proportion of invalid expressions because it will insert an operator at the very end of the string:

9+8*7*6*54/3-2/1-
-9-8-7*6+5/43/2+1
987+6/54321
98/7-6+5-4/321+
9*8/7/6/54-3/2-1
9/876*543/21
-9*8/76543*2-1-
-987/65-432+1*
9*8+7+65*432*1-
9876/5*43+21
9876-54321*
987/6-5-4/3-21/
9-8+7*65432+1
98765+432*1+
-9*8-7*65432-1+
9+87*6543*21
9-87*65*4-3-2*1
-987654-321+
98*76/54*32*1-
-9-876/5-432*1*
-987*654+321
9/87+6543*21
98-7654/3+21
-98*7-6-5*4321
98+7+6/5+4*3+2-1
-98+76+54*3/2+1/
9876543/21
-9-8+76-54321*
[download]

Not always, and so it can be expected to still produce occasional correct answers, but it will take much longer and somehow offends my sensibilities :)

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

[reply]
[d/l]