class Solution:
    def subarraySum(self, A: List[int], k: int) -> int:
        N=len(A)
        D=defaultdict(int)
        S=0
        ans=0
        D[0]=1
        for i in range(N):
            S+=A[i]
            if S-k in D:
                ans+=D[S-k]
            D[S]+=1
        return ans