Subarrays with sum K or target

- 
Input:
N = 5
Arr = {10 , 2, -2, -20, 10}
k = -10
Output: 3
Explaination: 
Subarrays: arr[0...3], arr[1...4], arr[3..4]
have sum exactly equal to -10.

class Solution{

    public:
    int findSubArraySum(int Arr[], int N, int k)
    {
        map<int,int>mp;
        int ans=0,sum=0;

        mp[0]=1;
       
        for(int i=0;i<N;i++)
        {
            sum+=Arr[i];

            if(mp.find(sum-k)!=mp.end())
            ans+=mp[sum-k];

            mp[sum]++;
        }
        return ans;
    }
};

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