买不到的数目（通俗易懂）

解题思路: 枚举（两层嵌套循环枚举）从输入两个数的乘积开始递减循环

注意事项:

参考代码:

#include<stdio.h>

int main()

{

    int m, n,a,p;

    scanf("%d%d", &m, &n);    //输入两个数m,n

    a = m * n;

    while (1)

    {

        p = 1;

        for (int i = 0; i <= n; i++)    //双层嵌套循环枚举

        {

            for (int j = 0; j <=m ; j++)

            {

                if (a%m==0||a%n==0||i * m + j * n == a)        //当a能被m或n整除时直接a--

               {    

                    a--;

                    p = 0;

                    break;

                }

            }

        }

        if (p == 1)break;    //当循环中a不满足条件时推出while循环

    }

    printf("%d", a);    //输出a

    return 0;

}