Palindrome Golf

Answer 1

Golfscript, 5 char

.-1%=

$ echo -n abacaba | ruby golfscript.rb palindrome.gs
1

$ echo -n deadbeef | ruby golfscript.rb palindrome.gs
0

Answer 2

Sadly, I'm unable to get under a thousand words...

(LabVIEW. Yeah, they'll let just about any hobo post here ;)

Answer 3

Haskell, 15 chars:

p=ap(==)reverse

More readable version, 16 chars:

p x=x==reverse x

Answer 4

(equal p (reverse p))

lisp. 18 characters.

ok, this is a special case. This would work if typed directly into a lisp interpreter and p was already defined.

otherwise, this would be necessary:

(defun g () (equal p (reverse p)))

28 characters.

Answer 5

My attempt in C (70 chars):

P(char*s){char*e=s+strlen(s)-1;while(s<e&&*s==*e)s++,e--;return s>=e;}

[Edit] Now actually working
[Edit 2] Reduced from 74 to 70 by using default int return

In response to some of the comments: I'm not sure if that preprocessor abuse counts - you could just define the whole thing on the command line and make the function one character.

Answer 6

Here's mine; it's written in a domain-specific language I invented, called 'palindrome'.

p

Edit: Less flippant version (i386 asm, AT&T syntax)

xor %eax, %eax
mov %esi, %edi
#cld    not necessary, assume DF=0 as per x86 ABI
repne scasb
scan:
    dec %edi
    cmpsb
    .byte 0x75, 6    #jnz (short) done
    dec %edi
    cmp %esi, %edi
    .byte 0x72, -9    #jb (short) scan
inc %eax
done:

16 bytes, string pointer goes in ESI, result is in EAX.