public class 无序数组二分查找 {
    public static int quickSortOneTime(int[] a, int i, int j)// 一趟快速排序
    {
        int high, low, key;
        high = j;
        low = i;
        key = a[low];
        while (low < high) {
            while (key <= a[high] && low < high) {
                high--;
            }

            if (low < high) {
                a[low] = a[high];
                low++;
            }
            while (key >= a[low] && low < high) {
                low++;
            }
            if (low < high) {
                a[high] = a[low];
                high--;
            }
        }
        a[high] = key;
        return high;

    }

    public static void twoDepart(int[] a, int i, int j, int values) {
        int mid = quickSortOneTime(a, i, j);
        System.out.println("mid = " + mid + " i = " + i + " j = " + j);
        System.out.println(i < j);
        if (i < j) {
            if (a[mid] == values) {
                System.out.println("ok, keyword is at " + mid);

            } else if (a[mid] < values) {
                i = mid + 1;
                twoDepart(a, i, j, values);
            } else if (a[mid] > values) {
                j = mid - 1;
                twoDepart(a, i, j, values);
            }
        } else if (i == j && a[mid] != values) {
            System.out.println("It doesn't exists");
        } else
            System.out.println("Finalily we find the keyword is at " + mid);

    }

    public static void main(String[] args) {
        int[] a = new int[] { 1, 4, 9, 3, 24, 21, 6, 9, 9, 7, 6, 5, 3 };
        int values = 4;
        twoDepart(a, 0, a.length - 1, values);
    }
}