# include<iostream> using namespace std; //关系式：gcd(a,b)=gcd(b,a%b) //结束条件：a%b==0,b int gcd(int a,int b){ if(a%b==0) return b; return gcd(b,a%b); } int main(){ int a,c; cin>>a>>c; cout<<gcd(a,c)<<endl; return 0; }