An integer array is called arithmetic if it consists of at least three elements and if the difference between any two consecutive elements is the same.
[1,3,5,7,9], [7,7,7,7], and [3,-1,-5,-9] are arithmetic sequences.Given an integer array nums, return the number of arithmetic subarrays of nums.
A subarray is a contiguous subsequence of the array.
Example 1:
Input: nums = [1,2,3,4] Output: 3 Explanation: We have 3 arithmetic slices in nums: [1, 2, 3], [2, 3, 4] and [1,2,3,4] itself.
Example 2:
Input: nums = [1] Output: 0
Constraints:
1 <= nums.length <= 5000-1000 <= nums[i] <= 1000