C (VS2005)
Number of Characters: 1360
Abuse of preprocessor and warnings for fun code layout (scroll down to see):
#include
#include
#include
#define b main
#define c(a) b(a,0)
#define d -1
#define e -2
#define g break
#define h case
#define hh h
#define hhh h
#define w(i) case i
#define i return
#define j switch
#define k float
#define l realloc
#define m sscanf
#define n int _
#define o char
#define t(u) #u
#define q(r) "%f" t(r) "n"
#define s while
#define v default
#define ex exit
#define W printf
#define x fn()
#define y strcat
#define z strcpy
#define Z strlen
char*p =0 ;k *b (n,o** a){k*f
;j(_){ hh e: i* p==40? (++p,c
(d )) :( f= l( 0,
4) ,m (p ,q (% ),
f,&_), p+=_ ,f ); hh
d:f=c( e);s (1 ){ j(
*p ++ ){ hh 0: hh
41 :i f; hh 43 :*
f+=*c( e) ;g ;h 45:*f= *f-*c(
e);g;h 42 :* f= *f**c( e);g;h
47:*f /=*c (e); g; v: c(0);}
}w(1): if(p&& printf (q (( "\\"))
,* c( d) )) g; hh 0: ex (W
(x )) ;v :p =( p?y: z)(l(p
,Z(1[ a] )+ (p ?Z(p )+
1:1)) ,1 [a ]) ;b (_ -1 ,a
+1 ); g; }i 0;};fn () {n =42,p=
43 ;i "Er" "ro" t( r) "\n";}