How can I add up how many ints are even in the same array??

I'v only started to learn c++ this year so maybe this is just a simple problem.

here is the question I was given:

Write a function of the form int countEvens(int[], int) that returns the number of even ints in a given array, when passed the array and the number of elements in the array. Remember the % "mod" operator computes the remainder, e.g. 5 % 2 is 1.

countEvens({2, 1, 2, 3, 4},5) → 3

countEvens({2, 2, 0},3) → 3

countEvens({1, 3, 5},3) → 0

I passed the array and used the "mod" operator to identify which elements are even.

my problem is that I don't know how to add up how many even elements are in the array. Can anyone help me?

my code so far just displays which numbers in the array are even, I want to display how many are even. Here is my code

Code:

` `

#include <cstdlib>

#include <iostream>

using namespace std;

int countEvens(int a[], int size)

{

int i;

for (i=0; i<size; i++)

{

if ((a[i]%2) == 0)

{

cout << a[i] << " is even" << endl;

}

}

}

int main()

{

int array[5] = {2,3,4,5,2};

countEvens(array,5);

system("PAUSE");

return EXIT_SUCCESS;

}