2432 Number Of Zero Filled Subarrays

Number of Zero-Filled Subarrays

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

class Solution:
    def zeroFilledSubarray(self, nums: List[int]) -> int:
        """
        count the number of contiguous 0s
        and store then in arr
        sum all values from 1 to n
        """
        res = []
        prev = False
        temp = 0
        for k in nums:
            if k == 0:
                temp += 1
            else:
                res.append(temp)
                temp = 0
        if temp > 0:
            res.append(temp)
        ans = 0
        print(res)
        for k in res:
            ans += int((k*(k+1))/2)
        return ans