#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 a(int c,int b){ if(b==0) return c; else return a(b,c%b); } int main(){ int b,c; cin>>b>>c; cout<<a(b,c); return 0; }