0930. Binary Subarrays With Sum

https://leetcode.com/problems/binary-subarrays-with-sum

Description

Given a binary array nums and an integer goal, return the number of non-empty subarrays with a sum goal.

A subarray is a contiguous part of the array.

Example 1:

**Input:** nums = [1,0,1,0,1], goal = 2
**Output:** 4
**Explanation:** The 4 subarrays are bolded and underlined below:
[**1,0,1**,0,1]
[**1,0,1,0**,1]
[1,**0,1,0,1**]
[1,0,**1,0,1**]

Example 2:

**Input:** nums = [0,0,0,0,0], goal = 0

**Output:** 15

Constraints:

• 1 <= nums.length <= 3 * 104

• nums[i] is either 0 or 1.

• 0 <= goal <= nums.length

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