http://kor.i2p/books/The%20C%20Programming%20Language%20by%20K&R/chapter1.html
#include < stdio.h > #define LOWER 0 /* lower limit of table */
#define UPPER 300 /* upper limit */
#define STEP 20 /* step size */
/* print Fahrenheit-Celsius table */
main()
{
int fahr;
for (fahr = LOWER; fahr < = UPPER; fahr = fahr + STEP)
printf("%3d %6.1f\n", fahr, (5.0/9.0)*(fahr-32));
} The quantities LOWER , UPPER and STEP are symbolic
constants, not variables, so they do...