Finding kth smallest number from n sorted arrays

Question

So, you have n sorted arrays (not necessarily of equal length), and you are to return the kth smallest element in the combined array (i.e the combined array formed by mergin

Answer 1

Please find the below C# code to Find the k-th Smallest Element in the Union of Two Sorted Arrays. Time Complexity : O(logk)

public int findKthElement(int k, int[] array1, int start1, int end1, int[] array2, int start2, int end2)
    {
        // if (k>m+n) exception
        if (k == 0)
        {
            return Math.Min(array1[start1], array2[start2]);
        }
        if (start1 == end1)
        {
            return array2[k];
        }
        if (start2 == end2)
        {
            return array1[k];
        }
        int mid = k / 2;
        int sub1 = Math.Min(mid, end1 - start1);
        int sub2 = Math.Min(mid, end2 - start2);
        if (array1[start1 + sub1] < array2[start2 + sub2])
        {
            return findKthElement(k - mid, array1, start1 + sub1, end1, array2, start2, end2);
        }
        else
        {
            return findKthElement(k - mid, array1, start1, end1, array2, start2 + sub2, end2);
        }
    }