/*----------------------------------------------------------------------
  File    : frac.c
  Contents: print a fraction with an arbitrary number of decimals
  Author  : Christian Borgelt
  History : 19.01.1998 file created
----------------------------------------------------------------------*/
#include <stdio.h>
#include <stdlib.h>

/*----------------------------------------------------------------------
  Functions
----------------------------------------------------------------------*/

int printfrac (int p, int q, int n)
{                               /* --- print a fraction p/q with an */
                                /*     arbitrary number of decimals */
  int c;                        /* character counter */

  c = printf("%i", p /q);       /* print integer part of fraction */
  if (n <= 0) return c;         /* if no decimals requested, abort */
  c += printf(".");             /* print decimal point */
  while (--n >= 0) {            /* while not all decimals printed */
    p = (p %q) *10;             /* compute the remainder of p/q, */
    c += printf("%i", p /q);    /* multiply it by 10 to obtain the */
  }                             /* next digit, and print the digit */
  return c;                     /* return number of printed chars */
}  /* printfrac() */

/*----------------------------------------------------------------------
For an explanation of this function see exc1-6.tex/exc1-c6.ps.
----------------------------------------------------------------------*/

int main (int argc, char *argv[])
{                               /* --- main function */
  int p, q;                     /* numerator and denominator */
  int n;                        /* number of decimal places */

  if (argc != 4) {              /* if wrong number of arguments given */
    printf("usage: %s p q n\n", argv[0]);
    printf("print the fraction p/q with n decimal places\n");
    return 0;                   /* print a usage message */
  }                             /* and abort the program */
  p = atoi(argv[1]);            /* convert command line */
  q = atoi(argv[2]);            /* arguments to */
  n = atoi(argv[3]);            /* integer numbers */
  if (p/q < 0) printf("-");     /* print a sign, if necessary */
  printfrac(abs(p), abs(q), n); /* print fraction */
  printf("\n");                 /* terminate output line */
  return 0;                     /* return 'ok' */
}  /* main() */