Thread: How to avoid writing more code in a function?

Good afternoon,

Consider the following function:

Code:

double calculate(){
  double ret;
  for (int a = 0; a<=10; a++){
    ret = 2*a;
  }
  return ret;
}

This is just a hypothetical function where a variable (here, ret) constantly changes its value.
Suppose I need to print the steps of the function; for example, print every value of ret, and put everything between parentheses:

Code:

double calculate(){
  double ret;
  printf("(");
  for (int a = 0; a<=10; a++){
    ret = 2*a;
    printf("%d", ret);
  }
  printf(")");
  return ret;
}

(codes not tested in a compiler)
So, in a few words, I have a function that makes calculations, and I want to output the result of each step of the calculation to a file. But the problem is that I don't want to "fill" the function with a lot of output functions, like sprintf, printf, fprintf... I just want the function to have the calculation procedure; otherwise, if I need to use the function somewhere else and didn't need the outputs, I would have to erase them all.
Any idea on how I could track and output the steps of the function and keep it "clean" from lines that output to screen/files?
Tell me if I'm not being very clear.
Thank you in advance.