算法题：将一个数组中所有奇数放前面和偶数放后面(不开辟新的内存空间)

package arithmetic;

import java.util.Arrays;

public class OddAndEven {

    public static void main(String[] args) {        
        int [] a={5,10,26,32,41,7,9,8,4,12,1};;
        int low = 0;
        int high = a.length-1;
        /**想法：
         * 1.遍历。将奇数放在左边，偶数放在右边
         * 2.先遍历左边，直到出现不是奇数的时候为止
         * 3.再遍历右边，直到出现不是偶数的时候为止
         * 4.交换位置
         */
         while(low < high) {
                int i = low;
                //从数组的左边开始遍历
                while(a[i]%2 != 0) {
                    low++;
                    i = low;
                }
                
                int index = i;//当前出现的偶数的位置下标
                i = high;
                //从数组的右边开始遍历
                while(a[i]%2 == 0) {
                    high--;
                    i = high;
                }
                //交换
                if(low < high) {
                    int tmp = a[index];
                    a[index] = a[i];
                    a[i] = tmp;
                }
            }
        System.out.println(Arrays.toString(a));
    }
}