/*
 * Assignment
 * Chapter 7
 * John Stile
 */
1. Explain what the follwoing accomplishes and how it works.
  while (getchar() != '\n' ); // read from stdin
                              // evalue if not newline
                              // do again

2. Using English phrases rather than C code, sketch out 
   the logic of a program that reads from stdin until it 
   finds an EOF, coutning all instances of the digit 4,
   the character s, and the character = in the input.
   However, if it finds a letter Q, processing stops
   and the program exits.


3) Compare and contrast the follwing: 
    while, do/while, switch, for, if, break, and continue.
 
Answer: 
  while tests first, executes block, reruns test.
  do/while  executes bock, runs test, returns to block.
  switch tests, executes block, exists switch with break.
  for sets a counter, runs a test, executes block, then increments, and repeat. 
  if tests first, executes block, and finishes. block only runs once.
  break is used to go to the end of a while, do/while, case/switch 

4) In the SELF TEST 2, you wrote a program called factor.c that
   calcuated the factorsials from 1 to 10.  Explain how each aspect 
   of the code works. 

Ansewr:

#include <stdio.h>  // include stdio.h functions when compiling
#define NUM 10  // define a macro, where NUM will be reaplced by 10
int main(void)  // header for function main
{
  int xx,yy ;  // declare 2 intigers 
  float factorial; // declare a float

  for ( xx=1; xx<=NUM; xx=(xx+1) ) // outer loop, count from 1 to 10
  {
    factorial=1; // zero out factorial 
    printf("%d!=\t",xx);  // first part of output, current number
    for (yy=xx; yy>0; yy=(yy-1) ) // cycle through 1 to current xx
    {
      printf("%d*", yy);  // print each yy with a * after the digit
      factorial=(factorial*yy);  // calcuate the factoria by adding another mutilplyer each iteration
    }
    printf("\b"); // print the backspace, this removes the * from the final yy for this iteration.
    printf(" = %.0f\n", factorial);  // print the final result 
  }

  return 0;  // return 0 to calling function
}