2348.Number of Zero-Filled Subarrays
===

###### tags: `Medium`,`Array`,`Math`

[2348. Number of Zero-Filled Subarrays](https://leetcode.com/problems/number-of-zero-filled-subarrays/)

### 題目描述

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.

### 範例

**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` <= 10^5^
* -10^9^ <= `nums[i]` <= 10^9^

### 解答
#### C++

class Solution {
public:
    long long zeroFilledSubarray(vector<int>& nums) {
        long long ans = 0, count = 0;
        for (auto num : nums) {
            if (num) count = 0;
            else count++;
            ans += count;
        }
        return ans;
    }
};

> [name=Yen-Chi Chen][time=Tue, Mar 21, 2023]

#### Python

class Solution:
    def zeroFilledSubarray(self, nums: List[int]) -> int:
        ans, count = 0, 0
        for n in nums:
            if n:
                count = 0
            else:
                count += 1
            ans += count
        return ans

> [name=Yen-Chi Chen][time=Tue, Mar 21, 2023]

#### Javascript

function zeroFilledSubarray(nums) {
  let countZero = 0;
  let result = 0;
  for (const num of nums) {
    if (num === 0) {
      countZero++;
    } else {
      countZero = 0;
    }
    result += countZero;
  }

  return result;
}

> [name=Marsgoat][time=Tue, Mar 21, 2023]

### Reference

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