1248. Count Number of Nice Subarrays 发表于 2022-01-11 1234567891011121314151617class Solution { public int numberOfSubarrays(int[] nums, int k) { int[] preArray = new int[nums.length + 1]; // 注意不要忘记多分配一个 preArray[0] = 1; int sum = 0, res = 0; for (int num : nums) { sum += num & 1; // 前缀数组奇数的个数 if (sum >= k) { res += preArray[sum - k]; } preArray[sum]++; } return res; }} Reference1248. Count Number of Nice Subarrays