Extremely large numbers showing up in output file - c++

Question

I have a program which takes in a data file full of numbers (5 digits - 1 digit), sorts it, then calculates the average.
Problem is, for some strange reason, I seem to be getting random numbers. For example, here's an example of the output file (it changes everytime for some reason):
-1634367306
-1461109043
-542664683
-542664639
-542664491
-2
-1
-1
0
0
And towards the end...
2003150324
2003165000
2003165000
2003165011
2003165011
2003165090
2003195799
2003196010
2003196054
2003284685
2003834952
2006176524
2006176524
2006221796
2006221796
The numbers from the input file are from 0 - 99999, so I have no clue why these numbers are showing up.
Here's my code concurrently for it:
#include <iostream>
#include <cmath>
#include <fstream>
using namespace std;
void getData(int[], int);
void outputData(int[], int);
double calcAverage(int[], int);
int findHighest(int[], int);
int findLowest(int[], int);
void removeDuplicates(int[], int);
void selectionSort (int[], int);
int main() {
const int SIZE = 1000;
int table[SIZE];
getData(table, SIZE);
selectionSort(table, SIZE);
cout << "Highest number: " << findHighest(table, SIZE) << endl;
cout << "Lowest number: " << findLowest(table, SIZE) << endl;
cout << "Average: " << calcAverage(table, SIZE) << endl;
outputData(table, SIZE);
}
/** selectionSort
** - Sorts an array of numbers
**/
void selectionSort(int array[], int size) {
int startScan, minIndex, minValue;
for (startScan = 0; startScan < (size - 1); startScan++) {
minIndex = startScan;
minValue = array[startScan];
for (int index = startScan + 1; index < size; index++) {
if (array[index] < minValue) {
minValue = array[index];
minIndex = index;
}
}
array[minIndex] = array[startScan];
array[startScan] = minValue;
}
}
/** getData
** - Opens a file of a set of numbers
** - Reads data from file into an array of numbers
**/
void getData(int table[], int size) {
ifstream iFile;
iFile.open("numbers.txt");
if (!iFile) {
cout << "File failed to load, please try again." << endl;
return;
}
for (int i = 0; i < size; i++) {
iFile >> table[i];
}
iFile.close();
}
/** outputData
** - outputs a sorted array of numbers to a text file
**/
void outputData(int table[], int size) {
ofstream oFile;
oFile.open("entry.txt");
for (int i = 0; i < size; i++) {
oFile << table[i] << endl;
}
oFile.close();
}
/** calcAverage
** - Calculate and return average of all data entries
**/
double calcAverage(int table[], int size) {
double total = 0;
for (int i = 0; i < size; i++) {
total += table[i];
}
return total / size;
}
/** findHighest
** - return highest number from array
**/
int findHighest(int table[], int size) {
int high = 0;
for (int i = 0; i < size; i++) {
if (table[i] > high)
high = table[i];
}
return high;
}
/** findLowest
** - return lowest number from array
**/
int findLowest(int table[], int size) {
int low = findHighest(table, size);
for (int i = 1; i < size; i++) {
if (table[i] < low)
low = table[i];
}
return low;
}
Typical results of the Highest, Lowest, Average, show:
Highest number: 2006221796 Lowest number: 2006221796 Average: 2.71055e
+ 007
No clue what I'm getting wrong here. No compiler errors, and I'm pretty sure everything was initialized properly.

Answer 1

'Input file is unordered, and has 921 lines of numbers' - so how your progam will know how many items were read into the array? You declare const int SIZE = 1000; and use that value as a range of sorting – so you're sorting 79 uninitialized items of the array, data which were not in your input,

Answer 2

Try writing your input routine something like this in order to determine the number of elements that were actually read in:
int getData(int table[], int maxsize) {
ifstream iFile("numbers.txt");
if (!iFile) {
cerr << "Can't open number.txt\n";
return 0;
}
int n, i = 0;
while (iFile >> n) {
if (i >= maxsize) {
cerr << "Table overflow\n";
break;
}
table[i++] = n;
}
iFile.close();
return i; // return the number of elements read
}