题目：输入两个正整数m和n，求其最大公约数和最小公倍数。
我输入75  35 结果是3 和75  为什么?

# include <stdio.h>

main ()
{
    int a, b, num1, num2,temp;
   
    printf("please input two numbers: \n");
   
    scanf("%d ,%d", &num1, num2);
   
    if (num1<num2)
    {
        temp = num1;
        num1 = num2;
        num2 = temp;
    }
   
    a = num1;
    b = num2;
   
    while(b != 0)
    {
        temp = a%b;
        a = b;
        b = temp;
    }
    printf ("gongyueshu:%d \n", a);
    printf ("goneyueshu:%d \n", num1*num2 / a);
    getchar ();
    return 0;
}

做过的作业， 经供参考！

root@~ #cat lx89.c
#include <stdio.h>
int gcd (int u,int v) {
        int temp;
        if(u<0||v<0) {
                u = -1;
                return u;
        }
        while (v!=0) {
                temp = u%v;
                u=v;
                v=temp;
        }
        return u;
}
int lcm (int u,int v) {
        int result;
        result=(u*v)/gcd(u,v);
        return result;
}
int main (void) {
        int u,v;
        int gcd (int u,int v);
        int lcm (int u,int v);

        printf ("Enter two digit:\n");
        scanf ("%i %i",&u,&v);

        printf ("gcd is:%i\nlcm is:%i\n",gcd(u,v),lcm(u,v));
        return 0;
}
root@~ #./lx89
Enter two digit:
75 35
gcd is:5
lcm is:525
root@~ #./lx89
Enter two digit:
1026 495
gcd is:9
lcm is:56430
root@~ #

楼上的写的不错

你的空格好多看着好空旷啊~~网上有个和你一摸一样的我敲进去结果和你一样直接复制他的就出来结果了，我也想知道为什么啊！！！

int a, b, num1, num2,temp;
   
    printf("please input two numbers: \n");
   
    scanf("%d%d", &num1,&num2);
   
    if (num1<num2)
    {
        temp = num1;
        num1 = num2;
        num2 = temp;
    }
   
    a = num1;
    b = num2;
   
    while(b != 0)
    {
        temp = a%b;
        a = b;
        b = temp;
    }
    printf ("gongyueshu:%d \n", a);
    printf ("gonebeishu:%d \n", num1*num2 / a);

#include <stdio.h>

int main()
{
    int a = 0,b = 0,c = 0;
    int i = 0,j = 0,k = 0;

    int na = 8,nb = 10;
    int min = na * nb;
    while(nb != 0)
    {
        int temp = na%nb;
        na = nb;
        nb = temp;
    }
    printf("%d\n",na);
    printf("%d\n",min/na);
    return 0;
}

最大公约 最小公倍数 都有了

你这个第6行中
 scanf("%d ,%d", &num1, num2);
num2前的取地址符号呢？

调试发现Num2没值？什么情况？

拿我的去调试

scanf("%d,%d", &num1, &num2);输入数据需要用逗号区隔，不能用回车