1063. Number of Valid Subarrays

https://leetcode.com/problems/number-of-valid-subarrays

Description

Given an integer array nums, return the number of non-empty subarrays with the leftmost element of the subarray not larger than other elements in the subarray.

A subarray is a contiguous part of an array.

Example 1:

**Input:** nums = [1,4,2,5,3]
**Output:** 11
**Explanation:** There are 11 valid subarrays: [1],[4],[2],[5],[3],[1,4],[2,5],[1,4,2],[2,5,3],[1,4,2,5],[1,4,2,5,3].

Example 2:

**Input:** nums = [3,2,1]
**Output:** 3
**Explanation:** The 3 valid subarrays are: [3],[2],[1].

Example 3:

**Input:** nums = [2,2,2]
**Output:** 6
**Explanation:** There are 6 valid subarrays: [2],[2],[2],[2,2],[2,2],[2,2,2].

Constraints:

• 1 <= nums.length <= 5 * 104

• 0 <= nums[i] <= 105

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