Welcome to Subscribe On Youtube

Formatted question description: https://leetcode.ca/all/2348.html

2348. Number of Zero-Filled Subarrays

• Difficulty: Medium.
• Related Topics: Array, Math.
• Similar Questions: Arithmetic Slices, Number of Smooth Descent Periods of a Stock.

Problem

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

Solution (Java, C++, Python)

• Java
• Python
• C++
• Go
• TypeScript

• 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;
      }
  }
  
  ############
  
  class Solution {
      public long zeroFilledSubarray(int[] nums) {
          long ans = 0;
          int cnt = 0;
          for (int v : nums) {
              cnt = v != 0 ? 0 : cnt + 1;
              ans += cnt;
          }
          return ans;
      }
  }
  

• class Solution:
      def zeroFilledSubarray(self, nums: List[int]) -> int:
          ans = cnt = 0
          for v in nums:
              cnt = 0 if v else cnt + 1
              ans += cnt
          return ans
  
  ############
  
  # 2348. Number of Zero-Filled Subarrays
  # https://leetcode.com/problems/number-of-zero-filled-subarrays/
  
  class Solution:
      def zeroFilledSubarray(self, nums: List[int]) -> int:
          res = curr = 0
          
          for x in nums:
              if x != 0:
                  curr = 0
              else:
                  curr += 1
                  res += curr
          
          return res
  
  

• class Solution {
  public:
      long long zeroFilledSubarray(vector<int>& nums) {
          long long ans = 0;
          int cnt = 0;
          for (int& v : nums) {
              cnt = v ? 0 : cnt + 1;
              ans += cnt;
          }
          return ans;
      }
  };
  

• func zeroFilledSubarray(nums []int) (ans int64) {
  	cnt := 0
  	for _, v := range nums {
  		if v != 0 {
  			cnt = 0
  		} else {
  			cnt++
  		}
  		ans += int64(cnt)
  	}
  	return
  }
  

• function zeroFilledSubarray(nums: number[]): number {
      let ans = 0;
      let cnt = 0;
      for (const v of nums) {
          cnt = v ? 0 : cnt + 1;
          ans += cnt;
      }
      return ans;
  }
  
  

Explain:

nope.

Complexity:

• Time complexity : O(n).
• Space complexity : O(n).

All Problems

All Solutions