PC^2/pc2board/samps/practice.c

   1
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4
   5 /*
   6  * File:    practice.c
   7  * Purpose: sum of positive integers practice problem
   8  * Author:  pc2@ecs.csus.edu
   9  *
  10  * $Id: practice.c,v 1.1 2005/03/06 05:34:39 laned Exp $
  11  */
  12
  13 #define INFILE "practice.in"
  14
  15 int main (int argc, char **argv)
  16 {
  17         int sum = 0;
  18         int i = 0;
  19         FILE *fp = fopen (INFILE,  "rt");
  20         char line[128];
  21
  22         if (fp != NULL)
  23         {
  24                 while ( fgets (line, sizeof(line), fp) != NULL)
  25                 {
  26                         long inval = atol (line);
  27                         sum = 0;
  28
  29                         if (inval == 0)
  30                                 exit (4);
  31
  32                         if (inval < 1)
  33                         {
  34                                 for (i = 1; i >= inval; i --)
  35                                        sum += i;
  36                         }
  37                         else
  38                         {
  39                                 for (i = 1; i <= inval; i ++)
  40                                        sum += i;
  41                         }
  42                         printf("N = %-3d    Sum = %d\n", inval, sum);
  43                 }
  44
  45                 printf("Did not find trailing zero \n");
  46
  47         }
  48         else
  49         {
  50                 fprintf(stderr,"Could not read file %s \n", INFILE);
  51         }
  52
  53         exit (4);
  54 }
  55
  56 /* eof practice.c */