Package g3701_3800.s3728_stable_subarrays_with_equal_boundary_and_interior_sum

Class Solution

java.lang.Object
g3701_3800.s3728_stable_subarrays_with_equal_boundary_and_interior_sum.Solution
public class Solution extends Object
3728 - Stable Subarrays With Equal Boundary and Interior Sum.

Medium

You are given an integer array capacity.

A non-empty subarrays capacity[l..r] is considered stable if:

  • Its length is at least 3.
  • The first and last elements are each equal to the sum of all elements strictly between them (i.e., capacity[l] = capacity[r] = capacity[l + 1] + capacity[l + 2] + ... + capacity[r - 1]).

Return an integer denoting the number of stable subarrays.

Example 1:

Input: capacity = [9,3,3,3,9]

Output: 2

Explanation:

  • [9,3,3,3,9] is stable because the first and last elements are both 9, and the sum of the elements strictly between them is 3 + 3 + 3 = 9.
  • [3,3,3] is stable because the first and last elements are both 3, and the sum of the elements strictly between them is 3.

Example 2:

Input: capacity = [1,2,3,4,5]

Output: 0

Explanation:

No subarray of length at least 3 has equal first and last elements, so the answer is 0.

Example 3:

Input: capacity = [-4,4,0,0,-8,-4]

Output: 1

Explanation:

[-4,4,0,0,-8,-4] is stable because the first and last elements are both -4, and the sum of the elements strictly between them is 4 + 0 + 0 + (-8) = -4

Constraints:

  • 3 <= capacity.length <= 105
  • -109 <= capacity[i] <= 109

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • countStableSubarrays

      public long countStableSubarrays(int[] capacity)