[Leet Code] Sort Array By Parity II

Leetcode: https://leetcode.com/problems/sort-array-by-parity-ii/

Problem:

Given an array A of non-negative integers, half of the integers in A are odd, and half of the integers are even.

Sort the array so that whenever A[i] is odd, i is odd; and whenever A[i] is even, i is even.

You may return any answer array that satisfies this condition.

Example 1:

Input: [4,2,5,7]
Output: [4,5,2,7]
Explanation: [4,7,2,5], [2,5,4,7], [2,7,4,5] would also have been accepted.

Note:

1. 2 <= A.length <= 20000
2. A.length % 2 == 0
3. 0 <= A[i] <= 1000

Solution:

class Solution(object):
    def sortArrayByParityII(self, A):
        """
        :type A: List[int]
        :rtype: List[int]
        """
        answers = [0] * len(A)
        even = 0
        odd = 1
        for i in A:
            if i % 2 == 0:
                answers[even] = i
                even += 2
            else:
                answers[odd] = i
                odd += 2
        return answers