/*-----------------------------------------------------
 Contract: main : void -> int
 Purpose: quickie switch example --- asks how many 
          grades are to be entered, then prompts
          the user for that many letter grades,
          counting how many of each are entered.
          Then prints a simple table of how many
          of each has been entered, and then the
          average of those grades (based on the classic
          A = 4.0, B = 3.0, etc., scale).

 Examples: If, when interactively prompted, the user
           enters 12, and then: A b q a C b G B D a f b
           then the program will print to the screen:

total number of grades entered: 12
number of A's: 3
number of B's: 4
number of C's: 1
number of D's: 1
number of F's: 1
number of bad entries: 2

Average of these letter grades: 2.7

by: Sharon M. Tuttle
last modified: 12-02-05
--------------------------------------------------------*/

#include <iostream>
#include "show_grade_freq.h"
#include "grade_avg.h"
using namespace std; 

int main()
{
    // declare variables
    const int NUM_LETTER_GRADES = 6;

    char curr_grade;
    
    int num_each[NUM_LETTER_GRADES];
    int num_grades;

    // initialize each num_each element to 0

    for (int i = 0; i < NUM_LETTER_GRADES; i++)
    {
        num_each[i] = 0;
    }

    // how many grades does the user want to enter?

    cout << "How many letter grades are to be entered? ";
    cin >> num_grades;

    // ask user for that many letter grades

    for (int i=0; i<num_grades; i++)
    {
	// ask user for a letter grade
	cout << "Please enter a letter grade: ";
	cin >> curr_grade;

	// increment appropriate grade counter in num_each
	switch(curr_grade)
	{
	    case 'A':
	    case 'a':
		num_each[0]++;
		break;
	    case 'B':
	    case 'b':
                num_each[1]++;
		break;
	    case 'C':   
	    case 'c':
                num_each[2]++;
		break;
	    case 'D':
	    case 'd':
                num_each[3]++;
		break;
	    case 'F':  
	    case 'f':
                num_each[4]++;
		break;
	    default:
		num_each[5]++;
		cout << "hey, NOT a grade!!!";
		cout << endl;
	}
    }

    // print out a report showing how many of each grade
    //     there are
    
    cout << endl
         << "total number of grades entered: " << num_grades 
         << endl;

    show_grade_freq(num_each, NUM_LETTER_GRADES);

    // print out the average of all the grades, on a
    //    4-point scale

    cout << endl
         << "Average of these letter grades: " 
         << grade_avg(num_each, NUM_LETTER_GRADES)
         << endl << endl;

    return EXIT_SUCCESS;
}