Introducing Loops

Listing 5.1 shows a sample program that does a little arithmetic to calculate the length in inches of a foot that wears a size 9 (men's) shoe. To enhance your appreciation of loops, this first version illustrates the limitations of programming without using a loop.

Listing 5.1. The shoes1.c Program
/* shoes1.c -- converts a shoe size to inches */
#include <stdio.h>
#define ADJUST 7.64
#define SCALE 0.325
int main(void)
{
  double shoe, foot;

  shoe = 9.0;
  foot = SCALE * shoe + ADJUST;
  printf("Shoe size (men's)    foot length\n");
  printf("%10.1f %15.2f inches\n", shoe, foot);
  return 0;
}

Here is a program with multiplication and addition. It takes your shoe size (if you wear a size 9) and tells you how long your foot is in inches. ...

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