Question

i have to write a method,
The method receives a parameter of two-dimensional array of integers. The method returns the number of the row which has the highest sum of the integers.I’m allowed to use only recursion! no loops allowed!-of course i need to make a private method that will sum a row as a single array and then i have to do another private method that compares the rows, but it doesn’t really work since the method i wrote is only for a 1d array, and i need to compare a row from a 2d array..

appreciate all kind of help..

some of my code:

private  int rowSum(int[] array, int index) {//the sum of an array(1d array)
        if (index == array.length)
            return 0;
        else
            return array[index] + rowSum(array, index + 1);
    }

**public int maxRow(int[][] a){------!!!---the problem...

    }**

Answer 1

Code:

public class MainClass {
    static  int contents[][] = { {1, 2 , 3, 4} , { 4, 5, 8, 7}, { 4, 2, 8, 7}, { 4, 5, 0, 7} };
    public static void main(String[] args) 
    {
        System.out.println(getIndexOfRowWithHighestSum(contents, 0, 0));
    }
    public static int getIndexOfRowWithHighestSum(int[][] twoDAray, int currentIndex,int indexWithHighestSum){
        if(currentIndex>=twoDAray.length){
            return indexWithHighestSum;
        }
        int sum1 = getSumOfArray(twoDAray[currentIndex], 0) ;
        int sum2 = getSumOfArray(twoDAray[indexWithHighestSum], 0);

        indexWithHighestSum = (sum1 > sum2)?currentIndex:indexWithHighestSum;

        return getIndexOfRowWithHighestSum(twoDAray, currentIndex+1,indexWithHighestSum);
    }
    public static int getSumOfArray(int[] array, int currentIndex){
        if(currentIndex>=array.length){
            return 0;
        }
        return array[currentIndex]+getSumOfArray(array,currentIndex+1);
    }
}