How to i get my Array to output its random generated values from 0 - 99

Question

I wanted to make a function called fillArray to set up random values to the Array. Then i wanted the function to output all the values but i kept getting values way above 99.

This is what i have written so far:

#include <ctime>
#include <iostream>

using namespace std;

void fillArray(){
    srand(time(NULL));

    const unsigned int sizeOfArray = 10; // this sets the array to the constant size of 10
    int numberArray[sizeOfArray];  //this sets the array to the size of 'sizeOfArray' which is 10

    for(int i = 0; i < sizeOfArray; i++)
    {
      numberArray[i] = rand() % 100;
      cout << numberArray[i] << endl;
    }
}


int main (){
    void fillArray(int a[10], int randNum);
    cout << numberArray[0] << " , " << numberArray[1] << " , " << numberArray[2] << " , " << numberArray[3] << " , " << numberArray[4] << " , " << numberArray[5] << " , " << numberArray[6] << " , " << numberArray[7] << " , " << numberArray[8] << " , " << numberArray[9] << '\n';

}

I understand the name numberArray hasnt been declared in the main function but just wondered what to do.

Answer 1

So, your error is simple:

You have declared a function in the main function like this:

int main()
{
  void fillArray(int a[10], int random);
}

But it should have been

int main()
{
  fillArray(int a[10], int random);
}

Which is calling the fillArray function Also there are a few other things that i would like to add,

instead of fillArray taking nothing it should take an array like this

  template<auto Size>
  void fillArray(int (&arr)[Size])
  {
    // Implemenatation
  }

and also, it should not take a random number the function can do that in the function body.

When you are printing your array, you should use a loop or a specialized function to do it like this:

template<auto Size>
auto PrintArray(int (&arr)[Size])
{
  for(int i = 0; i < Size; i++)
  {
    std::cout << arr[i] << ", ";
  }
  std::cout << "\n";
}

So, your final code would be something like the following:

#include <ctime>
#include <iostream>

using namespace std;

template<auto Size>
void fillArray(int (&numberArray)[Size]){
    srand(time(NULL));

    for(int i = 0; i < Size; i++)
    {
      numberArray[i] = rand() % 100;
    }
}

template<auto Size>
auto PrintArray(int (&arr)[Size])
{
  for(int i = 0; i < Size; i++)
  {
    std::cout << arr[i] << ", ";
  }
  std::cout << "\n";
}

int main (){
    int numberArray[10];
    void fillArray<10>(numberArray);
    PrintArray<10>(numberArray);

}