905. Sort Array By Parity

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

C#

public class Solution {
    public int[] SortArrayByParity(int[] nums) {
        var countEven = 0;
        for(int i = 0; i < nums.Length; i++){
            if(nums[i] % 2 == 0){
                (nums[i], nums[countEven]) = (nums[countEven], nums[i]);
                countEven++;
            }
        }
        return nums;
    }
}

• LINQ

public class Solution {
    public int[] SortArrayByParity(int[] nums) {
        var evenNumbers = nums.Where(n => n % 2 == 0);
        var oddNumbers = nums.Where(n => n % 2 == 1);
        return evenNumbers.Concat(oddNumbers).ToArray();
    }
}