leetcode905

class Solution {
    public int[] sortArrayByParity(int[] A) {
        int i=0;
        int j=A.length-1;
        while(i<j){
            while(i<j && A[i]%2==0){
                i++;
            }
            while(i<j && A[j]%2==1){
                j--;
            }
            if (i<j){
                int t = A[i];
                A[i] = A[j];
                A[j] = t;
            }
            i++;
            j--;
        }
        return A;
    }
}