[LeetCode force button 905] Sort the array by parity, given a non-negative integer array A, return an array in which all even elements of A are followed by all odd elements. You can return any array that meets this condition as the answer.

learning target:

Goal: proficiently use the knowledge learned in Java

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Subject content:

The content of this article: Implemented in Java: Sorting Arrays by Parity

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Title description:

Given an array of non-negative integers A, return an array in which all even elements of A are followed by all odd elements.

You can return any array that meets this condition as the answer.

Example:

Input: [3,1,2,4]
Output: [
2,4,3,1] Output [4,2,3,1], [2,4,1,3] and [4,2,1, 3] Will also be accepted.

Realize the idea:

This question is a disguised test of the sorting algorithm. You only need to change the conditions of the sorting algorithm. I will give you an idea of ​​a quick sorting algorithm here.

Implementation code:

public class Practice_02 {
    
    
    public static void main(String[] args) {
    
    
        int[] A={
    
    1,2,3,4,5,6};
        System.out.println(Arrays.toString(sortArrayByParity(A)));
    }
    public static int[] sortArrayByParity(int[] A) {
    
    
        int left = 0;
        int right = A.length - 1;
        while (left < right) {
    
    
            while ((left < right) && (A[right] % 2 != 0)) {
    
    
                right--;
            }
            while ((left < right) && (A[left] % 2 == 0)) {
    
    
                left++;
            }
            int temp = A[left];
            A[left] = A[right];
            A[right] = temp;
            right--;
            left++;
        }
        return A;
    }
}

operation result:

[6, 2, 4, 3, 5, 1]