C++ array assistance - c++

Question

I am getting an error in the word sum where it says average = sum / ARRAY_SIZE;. It is saying that the sum is undeclared. Even though I use sum previously in the getSum function, I only get the error here. I tried declaring it as a variable at the top but I am still getting that error. I do not know how else to declare it in a way that would stop this error.
#include <iostream>
#include <iomanip>
#include <fstream>
using namespace std;
// Function prototypes
int getHighest(int numbers[],int ARRAY_SIZE);
int getLowest(int numbers[],int ARRAY_SIZE);
int getSum(int numbers[],int ARRAY_SIZE);
int getAverage(int numbers[],int ARRAY_SIZE);
int main () {
// Variables
const int ARRAY_SIZE = 12; // Array size
int numbers [ARRAY_SIZE]; // Array with 12 integers
int count = 0; // loop counter variable
string filename;
// Open file
cout << "Enter input filename:";
cin >> filename;
ifstream inputFile(filename); // input file stream object
// Read numbers from file into array
while(count <ARRAY_SIZE && inputFile >> numbers[count])
count ++;
// Print results
cout<<ARRAY_SIZE<<" numbers read from input file."<<endl;
cout<<"The highest value is: "<<getHighest(numbers,ARRAY_SIZE)<<endl;
cout<<"The lowest value is: "<<getLowest(numbers,ARRAY_SIZE)<<endl;
cout<<"The sum of the numbers is: "<<getSum(numbers,ARRAY_SIZE)<<endl;
cout<<"The average of the numbers is: "<<getAverage(numbers,ARRAY_SIZE)<<endl;
}
int getHighest( const int numbers[], int ARRAY_SIZE)
{
int highest;
highest = numbers[0];
for(int count = 1 ; count < ARRAY_SIZE; count++)
{
if (numbers[count] > highest)
highest = numbers[count];
}
return highest;
}
int getLowest(const int numbers[], int ARRAY_SIZE)
{
int lowest;
lowest = numbers[0];
for (int count = 1; count < ARRAY_SIZE; count++)
{
if (numbers[count] < lowest)
lowest = numbers[count];
}
return lowest;
}
int getSum(const int numbers[], int ARRAY_SIZE)
{
int sum = 0;
for(int count = 0; count < ARRAY_SIZE; count++)
sum+= numbers[count];
return sum;
}
int getAverage(const int numbers[], int ARRAY_SIZE)
{
int average = 0;
for (int count = 0; count < ARRAY_SIZE; count++)
average = sum / ARRAY_SIZE;
return average;
}

Answer 1

It is saying that the sum is undeclared. Even though I use sum previously in the getSum function, I only get the error here.
sum is only a local variable in getSum so it cannot be accessed from getAverage, and in fact that variable does not exist anymore when you leave getSum
Note also the for in getAverage is useless because you do all the time average = sum / ARRAY_SIZE; whose value is always the same, so you want :
int getAverage(const int numbers[], int ARRAY_SIZE)
{
return getSum(numbers, ARRAY_SIZE) / ARRAY_SIZE;
}
Note your declarations and definitions do not correspond because in your definitions the array is const but not in your declarations. Put the array also const in the declarations :
int getHighest(const int numbers[],int ARRAY_SIZE);
int getLowest(const int numbers[],int ARRAYSIZE);
int getSum(const int numbers[],int SIZE);
int getAverage(const int numbers[],int SIZE);
may be also rename ARRAY_SIZE to size to not confuse with the global variable of the same name (even they receive its value), and SIZE to size because uppercase are generally not used to name a local variable/parameter.
Out of that, you are in C++, are you sure you want to use (C) arrays rather than for instance std::vector allowing to not give the size in argument to each functions and also to have iterators and predefined operations etc ?