#include<iostream>
using namespace std;
int a,b;
int c;
int main(){
cout<<"a=";cin>>a;
cout<<"b=";cin>>b;
while ((a!=0)&&(b!=0))
    {
     if  (a>=b) { a=a-b; }
     else             { b=b-a; }
     }
if (a==0)  c=b;
           else  c=a;
cout<<"cmmdc="<<c;
return 0;}