Write a function double average (int arr[], int n), that returns the average of the even elements of the array. If the array has no even elements, throw an integer-based exception containing the value 0. The number of elements in the array is specified by the parameter n.

double average (int arr[], int n) {

int evenElementCount = 0;

double sum = 0;

for (int i = 0; i < n; i++) {

if (arr [ i ] % 2 = = 0 && arr [ i ]! = 0) {

evenElementCount + = 1;

sum+=arr[i];

}

}

if (evenElementCount = = 0)

throw 0;

return sum/evenElementCount;

}

Explanation:

The Method called average takes in an array and number of elements, it loops through the array using a for-loop to find all the even elements in the array, it stores the number of even elements in a variable named evenElementCount, it throws an integer-based exception if the evenElementCount variable is 0, returns average of even elements if the evenElementCount variable is not 0.