Question

My program wont return boolean. There's nothing in the console.Here's the instructions:

Given an array of ints, compute recursively if the array contains somewhere a value followed in the array by that value times 10. We'll use the convention of considering only the part of the array that begins at the given index.In this way, a recursive call can pass index+1 to move down the array. The initial call will pass in index as 0.

examples are:

array220([1,2,20],0)----true

array220([3,30],0)----true

array220([3],0))----false

Here's my code:

public class timesTen {
   public static void main(String[] args) {

       int[] array = { 1, 2, 20, 9 };
       array220(array, 0);

   }

   public static boolean array220(int[] nums, int index) {

       if (index >= nums.length - 1)
           return false;
       if (nums[index] * 10 == nums[index + 1])
           return true;
       return array220(nums, index + 1);
   }
}

Answer 1

//here you are calling the function but not storing return result and also not printing.Either you should include function call in sysout statement or store the return result in a boolean variable and then print tht again. I have necessary change scheck now.

public class timesTen {
public static void main(String[] args) {

int[] array = { 1, 2, 20, 9 };
boolean result=array220(array, 0);
System.out.println(result);

}

public static boolean array220(int[] nums, int index) {

if (index >= nums.length - 1)
return false;
if (nums[index] * 10 == nums[index + 1])
return true;
return array220(nums, index + 1);
}
}