#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int w(int x,int y){ if(y==0) return x; return w(y,x%y); } int main(){ int a,b; cin>>a>>b; cout<<w(a,b)<<endl; return 0; }