C #define macros

Question

Here is what i have and I wonder how this works and what it actually does.

#define NUM 5
#define FTIMES(x)(x*5)

int main(void) {
    int j = 1;
    printf(\         


        

Answer 1

the preprocessor substitutes all NUM ocurrences in the code with 5, and all the FTIMES(x) with x * 5. The compiler then compiles the code.

Its just text substitution.