increments and decrements, to keep track of the total number of increments and decrements needed.nums1 and nums2.
i, calculate the difference diff between nums1[i] and nums2[i].diff is positive, add diff / k to decrements (after checking if diff is divisible by k).diff is negative, add the absolute value of diff / k to increments (after checking if diff is divisible by k).diff is not divisible by k, return -1.increments equals decrements, return increments.increments does not equal decrements, return -1.