array jibberish

[algoRichard]

So everyone knows when you try to print something in an array that doesnt belong, the screen prints out weird stuff. I made a program that takes a file, fills an array with 10 numbers, and prints only distinct numbers. So if there's a repeated number, the program replaces that number with a space. Once that's done, the program finally prints out what's left in the array which should be only distinct numbers. Anyway, here's my code.

#include <cstdlib>
#include <iostream>
#include <fstream>

const int MAX = 10;

using namespace std;

int main()
{
    int i, j, num[MAX];
    ifstream infile;
    infile.open("data.txt");

    if(!infile.is_open()) {
        cout << "\nERROR: Unable to open file" << endl;
        system("PAUSE");
        exit(1);
    }

    i = j = 0;
    while(!infile.eof() && infile >> num[i])
        i++;

    for(i=0; i<9; i++)
        for(j=i+1; j<=9; j++) {
            if(num[i]==num[j])
                num[j] = ' ';
        }

    for(i=0; i<=9; i++)
        if(num[i]!= ' ')
            cout << num[i] << " ";

    infile.close();
    system("PAUSE");
    return 0;
}

Let's say I want to make an array of 100 slots but only have the program take in 50 numbers (because there are only 50 numbers in the file). When I do that, I get the jibberish. The program works fine when I only make a file with exactly the amount of numbers that my array can hold. It actually still works with any size but I dont want the jibberish. What must be fixed?

[Athar]

When you have to deal with variable number of elements, you use vectors:

vector<int> numbers;
int number;
while (infile >> number)numbers.push_back(number);
for(size_t i=0  ; i<numbers.size(); i++)
for(size_t j=i+1; j<numbers.size(); j++)
{
    if(numbers[i]==numbers[j])
    {
        numbers[j] = 0;
    }
}

Also, you can't assign a "space" to an int variable - what happens is that the character will be converted to an integer (that would be 32 for a space in ASCII).

[Volatile Pulse]

Here:

while(!infile.eof() && infile >> num[i])
        i++;

Change i to another variable name, possibly arraySize. Then in your loops, loop until i < size. This will eliminate all of that "gibberish" because you quite frankly don't output it.

[algoRichard]

Greatly appreciate your help, the both of you! Program works efficiently and neatly now.