Comparing while and do loops

Introduction to C example from a Well House Consultants training course
More on Introduction to C [link]

Source code: ltab.c Module: C101

#include <stdio.h>

#define OLDRATE 15.0
#define NEWRATE 20.0

/*

All about the code ... here is the USER DOCUMENTATION ;-) ...

=head1 Receipe for Pear Melba

Take a peach melba. Remove Peaches. Add pears. Eat

=cut

OK - so we're cheating and using Perl's POD handler! But it does
mean that we have
        - C source
        - User comments
        - User documentation
ALL in the same file!

*/

main () {
        int counter;
        float oldnet, newnet;

        printf ("VAT Conversion 2day and 2morrow\n");

/* While - slightly longwinded way of doing it ... */

        counter = 0;
        while (counter < 10) {
                oldnet = counter * OLDRATE;
                newnet = counter * NEWRATE;
                printf ("Net %2d was %6.2f becomes %6.2f\n",
                                counter,oldnet,newnet);
                counter = counter + 1;
                }

/* Syntactic icing - "for" loop alternative */

        for (counter = 0; counter < 10; counter++) {
                oldnet = counter * OLDRATE;
                newnet = counter * NEWRATE;
                printf ("Net %2d was %6.2f becomes %6.2f\n",
                                counter,oldnet,newnet);
                }

        }

/* Sample Output

munchkin:c grahamellis$ ./ltab
VAT Conversion 2day and 2morrow
Net 0 was 0.00 becomes 0.00
Net 1 was 15.00 becomes 20.00
Net 2 was 35.00 becomes 40.00
Net 3 was 52.50 becomes 60.00
Net 4 was 70.00 becomes 80.00
Net 5 was 87.50 becomes 100.00
Net 6 was 105.00 becomes 120.00
Net 7 was 122.50 becomes 140.00
Net 8 was 140.00 becomes 160.00
Net 9 was 157.50 becomes 180.00
Net 0 was 0.00 becomes 0.00
Net 1 was 15.00 becomes 20.00
Net 2 was 35.00 becomes 40.00
Net 3 was 52.50 becomes 60.00
Net 4 was 70.00 becomes 80.00
Net 5 was 87.50 becomes 100.00
Net 6 was 105.00 becomes 120.00
Net 7 was 122.50 becomes 140.00
Net 8 was 140.00 becomes 160.00
Net 9 was 157.50 becomes 180.00
munchkin:c grahamellis$

*/

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This module and example are covered on the following public courses:
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* C and C++ Programming
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* C and C++ Programming
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