Subarray Sum Equals K

Problem Statement
Given an array of integers nums and an integer k, return the total number of continuous subarrays whose sum equals k. A subarray is a contiguous part of the array.[1][10]

Examples

• Input: nums =, k = 2[1] Output: 2
  Explanation: The subarrays are (indices 0-1) and (indices 1-2).[4][1]

• Input: nums =, k = 3[2][3][1] Output: 2
  Explanation: The subarrays are and.[3][2][4][1]

• Input: nums = [2,2,-4,1,1,2], k = -3
  Output: 1.[1]

Constraints

• 1 ≤ nums.length ≤ 2 × 10^4[1]
• -1000 ≤ nums[i] ≤ 1000[1]
• -10^7 ≤ k ≤ 10^7[1]