modify the program to use sub-functions

[fantasyfootball]

I already did this work but my teacher told me to post it on this site and see if anybody else got the same thing. Follow the steps


// Inclass functions
// Modify the program to use sub-functions
// 1. code step 3 in a function to prompt and get a grade; you may use
// either value returning function or pass by reference
// 2. code steps 4-9 in a sub-function to display a proper greeting
// based on the grade
// Use proper function names, return types, and parameters.

// Modify the spec to show the algorithm in main.

/***************************************************************************************
* Naritive: The program will display a greeting message based on the grade entered. It *
* should keep on running as long as user chooses to. *
* INPUT: grade - single letter *
* repeat or not - y or n *
* OUTPUT: a message depend on grade entered *
* CONSTRAINTS: grade must be a, b, c, d, e *
* CONSTANTS: display messages, see below *
* OPERATION: *
* 1. set repeat to y *
* 2. as long as repeat is y, do the following step 3-10 *
* 3. prompt and read grade *
* 4. if grade is a or A, display Excellent job! *
* 5. else if grade is b or B, display Very good! *
* 6. else if grade is c or C, display Keep up the good work! *
* 7 else if grade is d or D, display Try harder next time. *
* 8. else if grade is e or E, display Don't give up! *
* 9. else display Invalid input. *
* 10. prompt and read wether to repeat or not *
****************************************************************************************/

#include <iostream>
#include <conio.h>
using namespace std;

int main()
{
char grade; // letter grade
char again = 'y'; // again starts at y so the while loop will run

// as long as contents of again is y or Y
// everything within the while block will repeat
while(toupper(again) == 'Y')
{
cout << "\nEnter your grade: ";
cin >> grade;

// switch statement must have a block
// switch can only be used for intergral types
// switch follows the same as nested if-else-if
switch (grade)
{
// case 'a': and case 'A': means:
// grade equals to 'a' or 'A'?
case 'a':
case 'A':
cout << "\nExcellent job!\n";
// break is not required by compiler
// it's there to prevent fall-through
// if grade is 'a', it'll break out of the swtch block
break;
case 'b':
case 'B':
cout << "\nVery good!\n";
break;
case 'c':
case 'C':
cout << "\nKeep up the good work!\n";
break;
case 'd':
case 'D':
cout << "\nTry harder next time.\n";
break;
case 'e':
case 'E':
cout << "\nDon't give up!\n";
break;
// default case is like the final else clause
// default runs when all the above cases are not true
default:
cout << "\nInvalid input.\n";
}
// prompt for whether to run again or not
// it must be done within the loop so that
// contents in again is updated
cout << "\nRun again (y/n)? ";
cin >> again;
}

_getch();
return 0;
}

[jonnin]

sorry, but what was the question? Did you need help with this?

[fantasyfootball]

I need to modify this program to use sub-functions, code step 3 in a function to get a grade, code steps 4-9 in a sub-function to display a proper greeting based on grade, and I have to use proper function names, return types, and parameters.

[vijayan]

Well, you have written all the code that gets the work done. All that you need to do now is refactor it into separate functions.

step 3:

char get_grade()
{

    std::cout << "Enter your grade: " ;

    char grade ;
    std::cin >> grade ;

    return grade ;
}

steps 4 to 9:

void display_message( char grade )
{
    switch( grade )
    {
        case 'A' : case 'a' :
            std::cout << "Excellent job!\n" ; break ;
        case 'B' : case 'b' :
            std::cout << "Very good!\n" ; break ;
        case 'C' : case 'c' :
            std::cout << "Keep up the good work!\n" ; break ;
        case 'D' : case 'd' :
            std::cout << "Try harder next time.\n" ; break ;
        case 'E' : case 'e' :
            std::cout << "Don't give up!\n" ; break ;
        default :
            std::cout << "Invalid input.\n" ;
    }
}

and for good measure, step 10:

bool run_again()
{
    std::cout << "\nRun again (y/n)? " ;

    char again ;
    std::cin >> again ;

    return again == 'y' || again == 'Y' ;
}

now in main, all you have to do is run these functions in a loop:

int main()
{
    do
    {
        char grade = get_grade() ;

        display_message( grade ) ;

    } while( run_again() ) ;
}