Problems with Beginner Arrays, C++ - c++

Question

The assignment requires three functions. The user enters digits 0-9 until they enter a 10, which stops input, and counts each number, then outputs how many of each number has been counted. It should only output if the user entered a number for it.
My only problem is that for every element in the array that the user doesn't use, Xcode counts it as a 0, so the final output has an abnormally large amount of zeros. Everything else works fine.
here is my code
#include <iostream>
using namespace std;
// counter function prototype
void count(int[], int, int []);
// print function prototype
void print(int []);
int main()
{
// define variables and initialize arrays
const int SIZE=100;
int numbers[SIZE], counter[10], input;
// for loop to set all counter elements to 0
for (int assign = 0; assign < 10; assign++)
{
counter[assign]=0;
}
// for loop to collect data
for (int index=0 ; input != 10 ; index++)
{
cout << "Enter a number 0-9, or 10 to terminate: ";
cin >> input;
// while loop to ensure input is 0-10
while (input < 0 || input > 10)
{
cout << "Invalid, please enter 0-9 or 10 to terminate: ";
cin >> input;
}
// if statements to sort input
if (input >= 0 && input <=9)
{
numbers[index] = input;
}
}
// call count function
count(numbers, SIZE, counter);
// call print function
print(counter);
return 0;
}
// counter function
void count(int numbers[], int SIZE, int counter[])
{
// for loop of counter
for (int index = 0 ; index < 10 ; index++)
{
// for loop of numbers
for (int tracker=0 ; tracker < SIZE ; tracker++)
{
// if statement to count each number
if (index == numbers[tracker])
{
counter[index]++;
}
}
}
return;
}
// print function
void print(int counter[])
{
// for loop to print each element
for (int index=0 ; index < 10 ; index++)
{
// if statement to only print numbers that were entered
if (counter[index] > 0)
{
cout << "You entered " << counter[index] << ", " << index << "(s)" << endl;
}
}
return;
}

Answer 1

What you're referring to as "XCode count[ing] as a 0" is actually just the uninitialized value. Given that you've decided to restrict the user's input to 0-9, an easy way of solving this dilemma would be, immediately after you size the array, to iterate through the array and set each value to -1.
Thereafter, when the user finishes their input, instead of just couting every single value, only print it with a conditional like the following:
if (counter[index] != -1)
{
cout << "You entered " << counter[index] << ", " << index << "(s)" << endl;
}
Note that this is the kind of use case that's much better suited to something like a linked list or a vector. As it stands, you're not doing anything to resize the array, or guard against overflow, so if the user attempts to enter more than 100 numbers, you'll run into serious problems.

Answer 2

First off, this isn't an answer to your exact question, but rather a suggestion on how to write your code in a much simpler form.
I'm not going to write this for you, as it's an assignment, and a rather simple one. Looks like you have a good handle on things as far as coding goes.
Consider this:
You need to allow the user to enter 0-10, and count all 0-9's. An array has indices, and a integer of array 10, would hold those 10 numbers you're counting by the indices. Now you just have some empty ints sitting around, so why not use them to count?
A code hint:
++numbers[input];
Second hint: Don't forget to initialize everything to zero.