continuous-subarrays.py

class Solution:
    def continuousSubarrays(self, nums: List[int]) -> int:
        """
            You are given a 0-indexed integer array nums. A subarray of nums is called continuous if:

            Let i, i + 1, ..., j be the indices in the subarray. Then, for each pair of indices i <= i1, i2 <= j, 0 <= |nums[i1] - nums[i2]| <= 2.
            Return the total number of continuous subarrays.

            A subarray is a contiguous non-empty sequence of elements within an array.
        """
        freq = {}
        left = right = 0
        count = 0

        while right < len(nums):
            freq[nums[right]] = freq.get(nums[right], 0) + 1

            while max(freq) - min(freq) > 2:
                freq[nums[left]] -= 1
                if freq[nums[left]] == 0:
                    del freq[nums[left]]
                left += 1

            count += right - left + 1
            right += 1

        return count