count-number-of-nice-subarrays

Count number of nice subarrays

Problem link

Solutions

Solution.py

# https://leetcode.com/problems/count-number-of-nice-subarrays/

class Solution:
    def numberOfSubarrays(self, nums: List[int], k: int) -> int:
        cnt, cur, ret = {0: 1}, 0, 0
        for x in nums:
            cur += x & 1
            if cur >= k:
                ret += cnt[cur - k]
            cnt[cur] = 1 if x & 1 else cnt[cur] + 1
        return ret

Tags

• Prefix > Sum
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