Count Subarrays With a Given Sum
Given an integer array nums (values may be negative) and an integer k, return how many contiguous, non-empty subarrays sum to exactly k.
Example 1
Input: nums = [1, 1, 1], k = 2 Output: 2
Example 2
Input: nums = [1, 2, 3], k = 3 Output: 2 Explanation: [1, 2] and [3].
Constraints
- 1 <= nums.length <= 2 * 10^4
- -1000 <= nums[i] <= 1000
- -10^7 <= k <= 10^7
Hint 1
A subarray (i, j] sums to k when prefix[j] - prefix[i] = k.
Hint 2
Count how many times each prefix sum has occurred so far.
Good practice for: Data Scientist, Data Engineer, Machine Learning Engineer, AI Engineer (LLM & Generative AI), Backend Developer, Full Stack Developer, Site Reliability Engineer
Run checks your code on 2 sample tests. Submit runs all 8 tests, including hidden ones, and earns points. Use console.log to debug. Python's first run can take a few seconds while it starts.