Question

Consider the following two methods:

public static boolean isTrue(int n){

if (n <= 1)

         return false;

       for (int i = 2; i < n; i++){

         if (n % i == 0)

            return false;

}

       return true;

}

public static int Method(int[] numbers, int startIndex) {

if(startIndex >= numbers.length)

return 0;

if (isTrue(numbers[startIndex]))

     return 1 + Method(numbers, startIndex + 1);

else

     return Method(numbers, startIndex + 1);

}

What is the final return value of Method() if it is called with the following parameters: numbers = {1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13}, startIndex = 0

Answer 1

// TestCode.java
public class TestCode {
    public static boolean isTrue(int n){

        if (n <= 1)

            return false;

        for (int i = 2; i < n; i++){

            if (n % i == 0)

                return false;

        }

        return true;

    }

    public static int Method(int[] numbers, int startIndex) {

        if(startIndex >= numbers.length)

            return 0;

        if (isTrue(numbers[startIndex]))

            return 1 + Method(numbers, startIndex + 1);

        else

            return Method(numbers, startIndex + 1);

    }

    public static void main(String args[])
    {
        int numbers[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13};
        int startIndex = 0;

        System.out.println(Method(numbers,startIndex));
    }
}

6

the final return value of Method() if it is called with the following parameters: numbers = {1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13}, startIndex = 0 is 6