C++ Input Output Sorting - c++

Question

The assignment calls for using 3 input and 3 output files, but for now I am trying just one. The program is supposed to include a function template that sorts an array of values in ascending order. The function will receive an unordered array and will return an ordered array. The function isn't supposed to perform any input or output.
My code exists as the following:
#include <iostream>
#include <iostream>
#include <fstream>
using namespace std;
ifstream inNumbers("intTestRead.txt");
ofstream outNumbers("intTestWrite.txt");
template<typename int[], typename int> void SelectionSort(int[], int);
void SelectionSort(int v[], int n)
{
int iMin;
for (int i = 0; i < n - 1; i++)
{
iMin = i;
for (int j = i + 1; j < n; j++)
{
if (v[j] < v[iMin])
{
iMin = j;
}
}
int aux = v[i];
v[i] = v[iMin];
v[iMin] = aux;
}
}
void main()
{
int data[100];
int i;
int length = 0;
if (!inNumbers)
cerr << "intTestRead.txt file could not be opened" << endl;
for (i = 0; i < 100 && inNumbers; ++i)
{
inNumbers >> data[i];
if (inNumbers)
{
length += 1;
}
SelectionSort(data, length);
outNumbers << data[i] << endl;
}
}
I mainly program in Java, and now just beginning C++ confuses me with templates and whatnot. The sorting function was given to us by the professor. My reading file looks like this:
65 40 84 9 79 90 71 93 39 44
It's supposed to look like this:
9 39 40 44 65 71 79 84 90 93
But look's like this:
65
65
84
84
84
90
90
93
93
93
-858993460
^^ I know because I'm using endl results in the new lines, but multiple recursions of the same number + the -85 is putting me off. Any help would be greatly appreciated.

Answer 1

Don't call the sort function after each input. Just call it when all input is ready.
Something like:
void main()
{
int data[100];
int i;
int length = 0;
if (!inNumbers)
cerr << "intTestRead.txt file could not be opened" << endl;
for (i = 0; i < 100 && inNumbers; ++i)
{
inNumbers >> data[i];
if (inNumbers)
{
length += 1;
}
}
SelectionSort(data, length);
for (i = 0; i < length; ++i)
{
outNumbers << data[i] << endl;
}
}

Answer 2

Looked at it again, and used an alternative:
#include <iostream>
#include <iostream>
#include <fstream>
#define NUMBERS 10
using namespace std;
ifstream inNumbers("intTestRead.txt");
ofstream outNumbers("intTestWrite.txt");
template <class T>
void Swap(T& A, T& B)
{
T temp;
temp = A;
A = B;
B = temp;
}
template <class T>
void SelectionSort(T A[], int N)
{
T min;
int j, k, minIndex;
for (k = 0; k < N; k++) {
min = A[k]; minIndex = k;
for (j = k + 1; j < N; j++) {
if (A[j] < min) { min = A[j]; minIndex = j; }
}
Swap(A[k], A[minIndex]);
}
}
void main()
{
int data[100];
int i = 0;
if (!inNumbers)
cerr << "intTestRead.txt file could not be opened" << endl;
for (i = 0; i < NUMBERS && inNumbers; ++i)
{
inNumbers >> data[i];
}
SelectionSort(data, NUMBERS);
for (int i = 0; i < NUMBERS; ++i)
outNumbers << data[i] << endl;
}
Input:
65
40
84
9
79
90
71
93
39
44
Output:
9
39
40
44
65
71
79
84
90
93