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#include <iostream>
using namespace std;
int getgrades()
{
// ***********************************************************************
// These are local variables: they only exist inside this function.
// Other variables with the same name which are in other functions are
// different variables. You can think that there could be ten John Smith
// who have the same name, but are different persons.
// The rule is there can only be one of them in a specific function,
// otherwise the compiler can't understand which one you want to use.
int grades[10]; // <-- you don't need this one
int count = 0; // <-- you don't need this one
int total = 0;
// ***********************************************************************
// Just to clarify the situation to the user
cout << "Please, give me ten integer values.\n";
// The following is a similar, but slightly different situation:
// the variable "i" is an integer variable as the ones above, but its life
// will be even shorter: it only exists inside the for-loop. As soon as
// you exit the loop, it disappears.
for (int i = 0; i < 10; i++)
{
// You don't need "count". You've already got a variable which starts
// from 0 and increases at each iteration: it's "i".
// You can substitute the expression "i+1" for "count" inside
// the "cout" statement. It won't modify the value of "i".
count++;
cout << "Grade " << count << ": ";
// You don't need an array. You just need an integer variable, which
// will be filled with the value given by the user at any iteration.
// You can also define it here and its life will be the same as "i":
// it will disappear as soon as the for-loop finishes.
cin >> grades[i]; // you can use a simple integer variables here...
total += grades[i]; // ...and here
}
// Now you've get out from the for-loop.
// "i" doesn't exist any more. It means you could define a new "i"
// int i;
// and use it without conflicts.
// If you got rid of the array "grades" and substituted an integer variable
// for it, that one would be disappeared as well. Pretty useful, isn't it?
// Whereas "total" is still there, because it was defined before entering
// the for-loop (better to say: outside the for-loop).
cerr << total; // <-- do you need this for debug?
return total; // <-- well done: the value of total is sent back to the caller
}
// You don't need any of these arguments
// As it works now, averagegrades() doesn't need to return any value, so it
// shouldn't be declared "int".
// Do you want to modify it so that it returns the average value to main() in
// order to have main() print it out?
int averagegrades(int i, int count, int total)
{
// This is the first function called by main(). In this situation main()
// doesn't have any sensible value to pass to this function; therefore you
// don't need any of the declared arguments.
// The following instruction is formally correct, but fairly useless.
getgrades();
// Let's have a look at it together. You've called the function getgrades(),
// which asks the user the values you need. That's fine, but at the end
// getgrades() tries to send the total back to the called, i.e. this function.
// Now, where has that value got to? :-)
// Solution: you need an integer variable that receives the value returned
// by getgrades().
// You can call that variable "total", if you wish, even if there's already
// one variable named "total" inside getgrades(). That's a different function,
// therefore the compiler won't mix them up (it's important that *you* don't
// get confused by this: two variables with the same name declared inside
// two different functions are different variables which happen to share
// the same name, as well as their could be a namesake of yours somewhere
// who's not you).
// Note: jonnin's suggestion (not to have two variables with the same name)
// is a good piece of advice, but in the future you'll write such large
// programs you'll even not be able to remember if you had already
// used that name or not. So I think it would be better if you
// get used, by trials and errors, to have more than one variable
// with the same name, but in different "scopes" (functions, loops...).
// Now, if you have read up to here, please get back and correct the last
// statement so as it stores the value returned by getgrades() inside a
// local integer variable.
// Granted you've decided to call the variable which stores the value
// returned by getgrades() "total", the following line presents an error.
// if you write
// total /= 10;
// you tell the compiler: divide the value of "total" by ten, and then
// **store it again** inside "total".
// You don't need to store it again inside "total", because it'll be stored
// inside "average". You only need to divide it by 10.
int average = (total /= 10 );
// Again: let's make things clear for the user.
cout << "Total: " << total << '\n';
// Is it a percentage? I'm terrible at math, but I'm pretty sure it's not
// a percentage...
cout << "Average Grade: " << average << "%" << endl;
}
/**********************************************************************
* Add text here to describe what the function "main" does. Also don't forget
* to fill this out with meaningful text or YOU WILL LOSE POINTS.
***********************************************************************/
int main()
{
// ***********************************************************************
// You don't need any of these variables.
// Values will be obtained by the user in the function getgrades();
int total;
int grades[10];
int count;
int i;
// ***********************************************************************
// You don't need to pass any argument to averagegrades().
averagegrades(count, grades[i], total);
return 0;
}
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