Is Three Consecutive Odds easy or hard?

Three Consecutive Odds is classified as an Easy problem on LeetCode. The task involves basic array traversal and a simple parity check using modulo. It is commonly recommended for beginners learning array iteration and streak-counting patterns.

How to solve Three Consecutive Odds in O(n)?

Iterate through the array and track the number of consecutive odd elements. For each number, check num % 2. If the number is odd, increase a running counter; if it is even, reset the counter to zero. The moment the counter reaches three, return true. If the loop finishes without reaching three, return false.

What is the best approach for Three Consecutive Odds?

The iterative counter approach is the best solution. Traverse the array once and maintain a counter for consecutive odd numbers. Increment the counter when an odd number appears and reset it when an even number appears. When the counter reaches three, return true. This runs in O(n) time and O(1) space.

What data structure is used in Three Consecutive Odds?

The problem primarily uses an array traversal. No additional data structures such as hash maps or stacks are required. A simple integer counter or a fixed-size sliding window over the array is enough to detect three consecutive odd numbers.

What is the time complexity of Three Consecutive Odds?

The optimal time complexity is O(n), where n is the length of the array. The algorithm performs a single pass through the array while checking whether each element is odd. Only constant extra space is used, so the space complexity is O(1).

Three Consecutive Odds Python or Java solution approach?

Both Python and Java implementations follow the same logic: iterate through the array and track consecutive odd numbers using a counter. When the counter reaches three, return true. This approach keeps the runtime O(n) and uses constant space.

Is Three Consecutive Odds asked at Google, Amazon, or Meta?

Three Consecutive Odds is categorized as an easy array problem and is more commonly used for screening rounds or practice rather than advanced interviews. Similar patterns—such as detecting consecutive elements or streaks—appear in interviews at companies like Amazon and Google.

Description Hints 1 Solution Video 9:58

1550. Three Consecutive Odds

Easy69.3% acceptance5 companies

Given an integer array arr, return true if there are three consecutive odd numbers in the array. Otherwise, return false.

Example 1:

Input: arr = [2,6,4,1]
Output: false
Explanation: There are no three consecutive odds.

Example 2:

Input: arr = [1,2,34,3,4,5,7,23,12]
Output: true
Explanation: [5,7,23] are three consecutive odds.

Constraints:

1 <= arr.length <= 1000
1 <= arr[i] <= 1000

Asked at 5 companies

Dji

Google Amazon Meta Bloomberg

Topics

Array

Hints open one at a time

Hint 1

Check every three consecutive numbers in the array for parity.

9:58

Still stuck?Read 4 approaches, or watch a walkthrough.

Open solution

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1class Solution:
2    def threeConsecutiveOdds(self, arr: List[int]) -> bool:
3        

Starter codePython 3Spaces: 4

Examples

Case 1Case 2

Input

[2,6,4,1]

Input

[1,2,34,3,4,5,7,23,12]

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