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Leetcode
Easy
Arrays
Special Array I

Determine whether an array is special by checking that every pair of adjacent elements has opposite parity.

Acceptance 0%
Problem Statement

Given an integer array, decide whether it is special: every pair of adjacent elements must have different parity. In other words, as you scan from left to right, no two consecutive numbers may both be even or both be odd.

Return true if the array is special, otherwise return false.

Input Format

  • A single integer array nums.
  • nums[i] is an integer.

Output Format

  • Return a boolean value indicating whether the array is special.

Constraints

  • The array contains at least one element.
  • Check only adjacent pairs.
  • Use integer parity (x % 2).
Examples
Sample cases returned by the problem API.

Example 1

Input

nums = [1,2,3,4]

Output

true

Explanation

Each adjacent pair has opposite parity: (1,2), (2,3), and (3,4).

Example 2

Input

nums = [2,4,6]

Output

false

Explanation

The first pair (2,4) has the same parity, so the array is not special.

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