How to calculate the percentage of even numbers in an array?

Question

i am beginner and here is the method I am struggling with.

Write a method called percentEven that accepts an array of integers as a parameter and returns the percentage of even numbers in the array as a real number. For example, if the array stores the elements {6, 2, 9, 11, 3}, then your method should return 40.0. If the array contains no even elements or no elements at all, return 0.0.

here is what I have so far...

public static double percentEven(int[]a){
    int count = 0;
    double percent = 0.0;
    if (a.length > 0){
        for ( int i = 0; i < a.length; i++){
            if ( a[i] % 2 == 0){
                count++;
            }
        }
            percent  =(count/a.length)*100.0;
    }
            return percent;
}

i keep returning 0.0 when array contains a mix of even and odd elements but works fine for all even element array or all odd array? i can't see where the problem is? thanks in advance.

Answer 1

count/a.length returns 0 since you are dividing two ints, and the second operand is larger than the first. Change it to (double)count/a.length in order to perform floating point division.

Alternately, change the order of operations to :

percent = 100.0*count/a.length;