930. Binary Subarrays With Sum
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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.
Examples
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 * 104nums[i] is either 0 or 1.0 <= goal <= nums.length