Subarray Sum Equals K
Given an array of integers nums and an integer k, return the total number of subarrays whose sum equals to k.

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Subarray Sum Equals K
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Given an array of integers nums and an integer k, return the total number of subarrays whose sum equals to k.

Example 1:
Input: {"nums":[1,1,1],"k":2}
Output: 2
Constraints:

  • 1≤nums.length≤2×1041 \leq \text{nums.length} \leq 2 \times 10^4

  • −1000≤nums[i]≤1000-1000 \leq \text{nums}[i] \leq 1000

  • −107≤k≤107-10^7 \leq k \leq 10^7

Input
arr ={"nums":[1,1,1],"k":2}
nums (k = 2)101112
Current Sum:
0
Subarrays Found:
0
Prefix Sum Count
Prefix SumCount
01
Algorithm Insight:

If prefixSum[j] - prefixSum[i] = k, then subarray [i+1...j] has sum k.
We look for (currentSum - k) in our map to find valid starting points.

Variables
No variables to display
DepthFunction Call
1subarraySum(nums=[3], k=2)
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