905. Sort Array By Parity - Easy
Given an array A
of non-negative integers, return an array consisting of all the even elements of A
, followed by all the odd elements of A
.
You may return any answer array that satisfies this condition.
Example 1:
Input: [3,1,2,4]
Output: [2,4,3,1]
The outputs [4,2,3,1], [2,4,1,3], and [4,2,1,3] would also be accepted.
Note:
1 <= A.length <= 5000
0 <= A[i] <= 5000
time = O(n), space = O(1)
class Solution { public int[] sortArrayByParity(int[] A) { int i = 0, j = A.length - 1; while(i < j) { if(A[i] % 2 != 0 && A[j] % 2 == 0) { swap(A, i++, j--); } if(A[i] % 2 == 0) { i++; } if(A[j] % 2 != 0) { j--; } } return A; } public void swap(int[] A, int i, int j) { int tmp = A[i]; A[i] = A[j]; A[j] = tmp; } }