Pointers Relationship with local variable - c++

Question

This is the task that I have performed.
Write a C++ function which accepts an array of integers and the size of the array and finds :
a. Sum of the elements in the array
b. Average of the array elements
c. Minimum and maximum values in the array
In the main program, declare an array of 10 integers using dynamic memory allocation and call
the aforementioned function. Display the output of the function within the main. (Use call by
reference for output values).
//USER DEFINED FUNCTION " func "
void func(int arr[], int size, int *sum, int *avg, int *min, int *max)
{
*sum = 0;
*min = arr[0];
*max = arr[0];
*avg = 0;
//calculations for sum
for (int i = 0; i < size; i++)
{
*sum = *sum + arr[i];
}
//calculations for avg
*avg = *sum / size;
//calculations for minimum
for (int i = 0; i < size; i++)
{
if (*min > arr[i])
*min = arr[i];
}
//calculations for maximum
for (int i = 0; i < size; i++)
{
if (*max < arr[i])
{
*max = arr[i];
}
}
}
void main()
{
int *arr;
int size;
cout << "enter size of array " << endl;
cin >> size;
arr = (int*) calloc(size, sizeof(int));
for (int i = 0; i < size; i++)
{
cout << "enter element : " << endl;
cin >> arr[i];
}
int sum, avg, min, max;
func(arr, size, &sum, &avg, &min, &max);
cout << "sum is : " << sum << "\n avg is : " << avg << endl;
cout << "minimum is : " << min << endl;
cout << "the maximum is : " << max << endl;
getch();
}
Thats my code, its working fine and giving me desired results but is their any alternate for this as well because in the " func " body i am using *min,*max ,*avg because i have passed a value by pointer though i can simply pass value by reference and use " min " instead of " *min " . I want a suggestion on how to pass a value through pointer and yet dont use a dereference operator inside the body of user defined function like here its "func" .

Answer 1

You can use references to achieve what you need.
So your function declaration will change to
func(int arr[], int size, int &sum, int &avg, int &min, int &max)
And inside you can use the variables directly as min, max, avg etc.
In the main you will have to call as
func(arr, size, sum, avg, min, max);
Finally, I will suggest you to create local variables, do all the calculations in them and them finally assign the values to the references passed (This might be a bit optimized in most cases).

Answer 2

To reduce dereference-cluttering, use local variables for the computations and write to the parameters when you're done.
Example:
void sum(const std::vector<int>& numbers, int* result)
{
int total = 0;
for (auto i: numbers)
{
total += i;
}
*result = total;
}
This has a couple of other benefits in addition to readability:
It's faster, because there's no need to constantly read and write through an indirection. (References are just as bad as pointers in this regard.)
It leaves the out parameter unmodified if something throws an exception.