#include<stdio.h>
int fun1(int x,int y) //求最大公约数
    {
     int m,t;  
          if(y>x)
       {
           t=x;
           x=y;
           y=t;
       }
           while(y);
           {
             t=x%y;
             x=y;
             y=t;
           }
           m=x;  
   return m;
    }
 
int fun2(int x,int y)  //求最小公倍数
  {
   int m,n,t,p;
   
    p=x*y;
   while(y);
           {
             t=x%y;
             x=y;
             y=t;
           }
           m=x;
      n=p/m;
  return n;
  }
 
int main()     
{
int a,b;
scanf("%d%d",&a,&b);

printf("m=%d,n=%d\n",fun1(a,b),fun2(a,b));
return 0;
}

https://bbs.bccn.net/viewthread.php?tid=460698&page=1#pid2545244

对于楼主while的使用，表示膜拜~