Hi All. I'm using GCC until I use Linux, and I've always used the compiler and the C language just basically. I've been made too basic usage of pre-processor macros(some constants, conditionals, and other)... For my surprise, it works different than I've always imagined... To me, it simply "subst" the text at compile-time. Since I'm training to the ACM, I've been noted hints about using macros to make the processing fast. So I think it's happen because the macros are replaced at compile time... And just it. Bu I've been made some tests... By example... A macro: #define mul(X,Y) (X*Y) It makes the processing faster... But I've passed vars which I've obtained at the runtime! So I think: int a,b,c; cin>>a; cin>>b c=mul(a,b) The mul(a,b) is replaced by a*b; But... Why executing that a milion of times is faster than using the simple a*b itself??? It really happens? Why? Thanks in the advance! Bruno M. Guedes
