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Java-based LeetCode algorithm problem solutions, regularly updated

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package g2301_2400.s2348_number_of_zero_filled_subarrays;

// #Medium #Array #Math #2022_07_30_Time_3_ms_(99.90%)_Space_59.8_MB_(95.67%)

/**
 * 2348 - Number of Zero-Filled Subarrays\.
 *
 * Medium
 *
 * Given an integer array `nums`, return _the number of **subarrays** filled with_ `0`.
 *
 * A **subarray** is a contiguous non-empty sequence of elements within an array.
 *
 * **Example 1:**
 *
 * **Input:** nums = [1,3,0,0,2,0,0,4]
 *
 * **Output:** 6
 *
 * **Explanation:**
 *
 * There are 4 occurrences of [0] as a subarray.
 *
 * There are 2 occurrences of [0,0] as a subarray.
 *
 * There is no occurrence of a subarray with a size more than 2 filled with 0. Therefore, we return 6.
 *
 * **Example 2:**
 *
 * **Input:** nums = [0,0,0,2,0,0]
 *
 * **Output:** 9
 *
 * **Explanation:**
 *
 * There are 5 occurrences of [0] as a subarray.
 *
 * There are 3 occurrences of [0,0] as a subarray.
 *
 * There is 1 occurrence of [0,0,0] as a subarray.
 *
 * There is no occurrence of a subarray with a size more than 3 filled with 0. Therefore, we return 9. 
 *
 * **Example 3:**
 *
 * **Input:** nums = [2,10,2019]
 *
 * **Output:** 0
 *
 * **Explanation:** There is no subarray filled with 0. Therefore, we return 0. 
 *
 * **Constraints:**
 *
 * *   1 <= nums.length <= 10⁵
 * *   -10⁹ <= nums[i] <= 10⁹
**/
public class Solution {
    public long zeroFilledSubarray(int[] nums) {
        long cnt = 0L;
        long local = 0L;
        for (int n : nums) {
            if (n == 0) {
                cnt += ++local;
            } else {
                local = 0;
            }
        }
        return cnt;
    }
}