#include 
int main(){   int num1,num2;   printf("请输入两个整数:");   scanf("%d%d",&num1,&num2);   while(num1%num2)   {      int r=num1%num2;//运用辗转相除法      num1=num2;      num2=r;   }   printf("%d\n",num2);   return 0;}