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