3618 - Split Array by Prime Indices.

Medium

You are given an integer array nums.

Split nums into two arrays A and B using the following rule:

• Elements at prime indices in nums must go into array A.

• All other elements must go into array B.

Return the absolute difference between the sums of the two arrays: |sum(A) - sum(B)|.

Note: An empty array has a sum of 0.

Example 1:

Input: nums = 2,3,4

Output: 1

Explanation:

• The only prime index in the array is 2, so nums[2] = 4 is placed in array A.

• The remaining elements, nums[0] = 2 and nums[1] = 3 are placed in array B.

• sum(A) = 4, sum(B) = 2 + 3 = 5.

• The absolute difference is |4 - 5| = 1.

Example 2:

Input: nums = -1,5,7,0

Output: 3

Explanation:

• The prime indices in the array are 2 and 3, so nums[2] = 7 and nums[3] = 0 are placed in array A.

• The remaining elements, nums[0] = -1 and nums[1] = 5 are placed in array B.

• sum(A) = 7 + 0 = 7, sum(B) = -1 + 5 = 4.

• The absolute difference is |7 - 4| = 3.

Constraints:

• <code>1 <= nums.length <= 10⁵</code>

• <code>-10⁹<= numsi<= 10⁹</code>