binary_subarr_sum.py (754B)
| # 930. Binary Subarrays With Sum
import collections
"""
given a binary array 'nums' and an integer 'goal', return the number o
non-empty subarrays with a sum 'goal'. a subarray is a contiguous part of the
array
"""
class Solution(object):
def numSubarraysWithSum(self, nums, goal):
"""
:type nums: List[int]
:type goal: int
:rtype: int
"""
c = collections.Counter({0: 1})
psum = ans = 0
for i in nums:
psum += i
ans += c[psum - goal]
c[psum] += 1
return ans
if __name__ == "__main__":
obj = Solution()
print(obj.numSubarraysWithSum(nums=[1, 0, 1, 0, 1], goal=2))
print(obj.numSubarraysWithSum(nums=[0, 0, 0, 0, 0], goal=0))
|
