Using a do-while loop and function calls

    int a = 0, b = 1, c = 0               /* initialize the series to 0, 1 */
    int sum();                              /* declare function to calc sums */

    printf("%5d \n", a);
    printf("%5d \n", b);


     c = sum(a, b);
     printf("%5d\n", c);
     a = b;
     b = c;

     while (c < 10000);


int sum (x, y) /* the parameters x and y receive the values of */
int x, y;          /* the two arguments passed by sum(a, b) in main() */


    return x + y;


Question: I need to use a subtract function to calculate and display the differences between the suceeding numbers in the fibonacci series.
I need to calculate and display thr quotients of the succeding fibonacci series in a third data column, right next to the differences.  For the divisions I need a division function named divide to perform this calculation.  To preserve the decimal accuracy of thequotients I will need to declare and use a float type function with two arguments  
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RONSLOWConnect With a Mentor Commented:
KangaRoo: Because it is a school/college/uni assignment? :-)

mvjohn: for accuracy, use a double, not a float type.  float types are not much use (except to save memeory when you are using a LOT of them).

Also, you are using yucky old-style C declarations.  This is bad programming practice.  You should declare your sum function as:

  int sum (int x, int y);

and define it as:

  int sum (int x, int y) {
    return x+y;

I think, without giving too much away, your subtract and divide functions would be

  int subtract (int x, int y) {
    return x-y;

  double divide (double x, double y) {
    return x/y;

then you'd change
  printf("%5d\n", c);
  printf("%5d %5d %8.5f\n", c, subtract(c,b), divide(c,b));

PS: you'll probaby want to put some error checking in the divide routine to avoid division by zero.

When the new number is calculated, the old number remains in b, so the difference could be obtained from c - b, which is probably equal to a, provided that sum(a,b) calculates a + b ... The quotient is double(c) / b. I don't see why you would need functions for these simple expressions
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