Minimum Swaps to Sort by Digit Sum
You are given an array nums of distinct positive integers. You need to sort the array in increasing order based on the sum of the digits of each number. If two numbers have the same digit sum, the smaller number appears first in the sorted order.
Return the minimum number of swaps required to rearrange nums into this sorted order.
A swap is defined as exchanging the values at two distinct positions in the array.
Example 1
Input
nums = [37,100]Output
1Sorting by digit sum produces
[100, 37], so one swap between 37 and 100 is required.Example 2
Input
nums = [22,14,33,7]Output
0The digit sums are already in increasing order, so
nums is already sorted and no swaps are needed.Constraints
- 1 <= nums.length <= 10^5
- 1 <= nums[i] <= 10^9
- nums consists of distinct positive integers.