#include <stdio.h>
int   old_number;     /* previous Fibonacci number */

int   current_number; /* current Fibonacci number */

int   next_number;    /* next number in the series */

main()
{
    /* start things out */
    old_number = 1;
    current_number = 1;

    (void)printf("1\n");    /* Print first number */

    while (current_number < 100) {

        (void) printf("%d\n", current_number);
        next_number = current_number + old_number;

        old_number = current_number;
        current_number = next_number;
    }
    return (0);
}


syntax highlighted by Code2HTML, v. 0.9.1