#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 z(int x,int y) { if(y==0)return x; return z(y,x%y); } int main(){ int x,y; cin>>x>>y; cout<<z(x,y)<<endl; return 0; }