Problem Statement

Given an integer array nums, move all the even integers at the beginning of the array followed by all the odd integers.

Return any array that satisfies this condition.

Example 1:

Input: nums = [3,1,2,4]
Output: [2,4,3,1]
Explanation: The outputs [4,2,3,1], [2,4,1,3], and [4,2,1,3] would also be accepted.

Example 2:

Input: nums = [0]
Output: [0]

Constraints:

• 1 <= nums.length <= 5000
• 0 <= nums[i] <= 5000

Problem Link

Sort Array By Parity - LeetCode

Code

class Solution {
public:
    vector<int> sortArrayByParity(vector<int>& nums) {
        
        int n = nums.size();
        
        for(int i=0,j=0;i<n;i++)
        {
            if(nums[i]%2==0)
                swap(nums[i],nums[j++]);
        }
        
        return nums;
    }
};