int main()

{

    //利用嵌套循环乘法口诀表

    for (int n = 1; n <= 9; n++)

    {

        for (int m = 1;  m <= n ; m++)

        {

            cout << m << "*" << n << "=" << m * n<<"  ";  //即使是单字符也要使用双引号切记！！

        }

        cout << endl;

    }

    system("pause");

    return 0;

    int a[] = {1,4,5,3,6,7};

    int b = sizeof(a) / sizeof(a[0]);//数组长度

    cout << "数组逆置前：" << endl;

    for (int i = 0; i < b; i++)

    {

        cout << a[i] << endl;

    }

    int start = 0;//数组起始位置

    int end = b-1;//数组末尾位置

    for ( ; start < end;)

    {

        //元素互换

        int temp = a[start];

        a[start] = a[end];

        a[end] = temp;

        start++;

        end--;

    }

    cout << "数组逆置后：" << endl;

    for (int i = 0; i < b; i++)

    {

        cout << a[i] << endl;

    }