Question

I’m new to Java and working on a basic program that looks through an array and gives prints the amount of numbers in the array that are divisible by 3. I’m having some trouble getting it to work right. Here is the code that I’ve got so far.

package arraysearch;

public class Intsearch {

    public static void main(String[] args) {

    }

    public static void multiple_3 (int[] a, int b)  {
        b=0;        
    }
    {
        int[] numarray ={3, 9, 45, 88, 23, 27, 68};
        {
            if (numarray % 3)==0;
                b = b+1;
        }
        System.out.println("This is the amount of numbers divisible by 3:" +b)
    }   
}

Answer 1

Try this (Java 7):

public static void main(String[] args) {
    multiple_3(new int[] { 3, 9, 45, 88, 23, 27, 68 });
}

public static void multiple_3(int[] ints) {
    int count = 0;
    for (int n : ints) {
        if (n % 3 == 0) {
            count++;
        }
    }
    System.out.println("This is the amount of numbers divisible by 3: " + count);
}

---

Java 8 update:

public static void multiple_3(int[] ints) {
    long count = IntStream.of(ints).filter(n -> n % 3 == 0).count();
    System.out.println("This is the amount of numbers divisible by 3: " + count);
}