//二分法查找
    int query(int arr[], int value) {
        int min = 0, max = 9, middle;
        while (min <= max) {
            middle = (min + max) / 2;
            if (arr[middle] > value) {
                max = middle - 1;
            } else if (arr[middle] < value) {
                min = middle + 1;
            } else {
                return middle;
            }
        }
        return -1;
    }