Program Requirements:
Let A be an array of n elements. Write a template function that takes an unsorted array of type <class T> as an input parameter and feeds back a sorted array via the input parameter. Assume the operators < and > are defined for the class T. In this question, you may hardcode n=5. You must write all functions you call, and also needs to write a main() to test the following data arrays stored in a data file (data.txt):

1 9 3 4 6
4 1 9 3 6
1.1 4.1 3.1 5.2 6.3
t d b e f

I have got my program to run but the output only shows me this:

The initial list is 1 9 3 4 6
The sorted list is

Can anyone help me fix this problem. I think that my SortedList function is correctly set up but I am not sure why it is not giving me the correct output. I was hoping you guys could locate any of my errors or give me any advice. This is my first time learning templates so any help would be appreciated. Thanks

#include <iostream>
#include <fstream>
#include <string>
using namespace std;
#define MAX_ELEMENTS 5
template < class T > void SortedList(T data[MAX_ELEMENTS])
{
// Sort the list
    for (int count1 = 0; count1 < MAX_ELEMENTS; count1++) {
	for (int count2 = 0; count2 < MAX_ELEMENTS; count2++) {
	    if (data[count2] > data[count2 + 1]) {
		T temp = data[count2 + 1];
		data[count2 + 1] = data[count2];
		data[count2] = temp;
	    }
	}
    }
}

int main()
{
    string data[5];
    string temp;
    ifstream infile;
    infile.open("data.txt");
    if (!infile)
	cout << "Your file was not opened correctly";
    else
	while (!infile.eof()) {
	    for (int i = 0; i < MAX_ELEMENTS && !infile.eof(); i++) {
		infile >> data[i];
	    }
	    cout << "The initial list is ";
	    for (int i = 0; i < MAX_ELEMENTS; i++) {
		cout << data[i] << " ";
	    }
	    cout << endl;
	    cout << "Sorted list is " << endl;
	    SortedList(data);



	    infile.close();
	    system("pause");
	    return 0;
	}
}
cout << "Sorted list is " << endl;
SortedList(data); //HERE

You need to cout this.

I did what you said and added a cout statement but now I am getting this error.

error C2679: binary '<<' : no operator found which takes a right-hand operand of type 'void' (or there is no acceptable conversion)

Here is my code again:

#include <iostream>
#include <fstream>
#include <string>
using namespace std;
#define MAX_ELEMENTS 5
template<class T>
void SortedList(T data[MAX_ELEMENTS])
{
    // Sort the list
    for(int count1=0; count1 < MAX_ELEMENTS;count1++)
    {
        for(int count2=0; count2 < MAX_ELEMENTS; count2++)
        {
            if(data[count2] > data[count2+1])
            {
                T temp=data[count2+1];
                data[count2+1]=data[count2];
                data[count2]=temp;
				
            }

        }
    }

}

int main()
{
    string data[5];
    string temp;
	string y;
    ifstream infile;
    infile.open("data.txt");
    if(!infile)
    cout<<"Your file was not opened correctly";
    else
    while(!infile.eof())
    {
    for(int i=0; i < MAX_ELEMENTS && !infile.eof(); i++)
    {
        infile>> data[i];
    }
    cout<<"The initial list is ";
    for(int i=0; i < MAX_ELEMENTS; i++)
    {
        cout<<data[i]<<" ";
    }
	cout<<endl;
	cout<<"The sorted list is ";
	cout<<SortedList(data); 
	infile.close(); 

    system("pause");
    return 0;
	}
}

The reason is that your function is of type "void", and does not return anything, so you can print it. Change the type of the list or whatever you are returning.

OK, I revised my code and changed the type of the list. But now my output is:
The initial list is 1 9 3 4 6
The sorted list is 3

CODE:

#include <iostream>
#include <fstream>
#include <string>
using namespace std;
#define MAX_ELEMENTS 5
template<class T>
string SortedList(T data[MAX_ELEMENTS])
{
    // Sort the list
    for(int count1=0; count1 < MAX_ELEMENTS;count1++)
    {
        for(int count2=0; count2 < MAX_ELEMENTS; count2++)
        {
            if(data[count2] > data[count2+1])
            {
                T temp=data[count2+1];
                data[count2+1]=data[count2];
                data[count2]=temp;
				return temp;
				
            }
        }
    }

}

int main()
{
    string data[5];
    string temp;
    ifstream infile;
    infile.open("data.txt");
    if(!infile)
    cout<<"Your file was not opened correctly";
    else
    while(!infile.eof())
    {
    for(int i=0; i < MAX_ELEMENTS && !infile.eof(); i++)
    {
        infile>> data[i];
    }
    cout<<"The initial list is ";
    for(int i=0; i < MAX_ELEMENTS; i++)
    {
        cout<<data[i]<<" ";
    }
	cout<<endl;
	cout<<"The sorted list is ";
	cout<<SortedList(data); 
	infile.close(); 

    system("pause");
    return 0;
	}
}

This is because you are returning "temp", which is in a for loop, and is constantly over-written. You need an array outside of the for loops which you write each sorted part of the list to, and then return that.

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