BinarySearch

class BinarySearchAlgorithm 
{
    public static int recursiveBinarySearch(int[] list, int low, int high, int key)
    {
        if( low >= high)
        {
            return -1;
        }
        int middle = low + (high - low) / 2;
        if(list[middle] == key)
        {
            return middle;
        }
        else if(list[middle] < key)
        {    
            low = middle + 1;
            return recursiveBinarySearch(list, low, high, key);
        }
        else 
        {
            high = middle - 1;
            return recursiveBinarySearch(list, low, high, key);
        }
    }
 
    public static int iterativeBinarySearch(int[] list, int low, int high, int key)
    {
        while(low <= high)
        {
            int middle = low + (high - low) / 2;
            if(list[middle] ==  key)
            {
                return middle;
            }
            else if(list[middle] < key)
            {
                low = middle + 1;
            }
            else 
            {
                high  = middle - 1;
            }    
        }
        return -1;
    }
 
    public static void main(String[] args) 
    {
        int[] list = {1, 3, 4, 6, 7, 9, 10, 11, 13};
        
        int recursiveBinarySearchResult = recursiveBinarySearch(list, 0, list.length - 1, 6);
        if(recursiveBinarySearchResult == -1)
        {
            System.out.println("The item does not exist in the list");
        }
        else 
        {
            System.out.println("The item found at index : " + result);
        }
        
        int iterativeBinarySearchResult = iterativeBinarySearch(list, 0, list.length - 1, 12);
        if(iterativeBinarySearchResult == -1)
        {
            System.out.println("The item does not exist in the list");
        }
        else 
        {
            System.out.println("The item found at index : " + result);
        }
    }
}