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Leetcode
Easy
Arrays
Sorting
Sort Array By Parity
Reorder an array so that all even numbers come before all odd numbers.
Acceptance 0%
Problem Statement
Given an integer array, rearrange its elements so that every even number appears before every odd number. The relative order within the even group and the odd group does not need to be preserved unless a follow-up asks for stability.
Return any valid reordered array.
Input Format
- An integer array
nums. - Each element may be positive, negative, or zero.
Output Format
- Return the same array rearranged so that all even elements appear before all odd elements.
Constraints
- The array length can be zero or more.
- A valid arrangement must place every even number before every odd number.
- Stability is not required for the standard version of the problem.
Examples
Sample cases returned by the problem API.
Example 1
Input
nums = [3,1,2,4]
Output
[2,4,3,1]
Explanation
The even numbers 2 and 4 are moved to the front, followed by the odd numbers 3 and 1.
Example 2
Input
nums = [0]
Output
[0]
Explanation
Zero is even, so the array is already valid.
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