#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 main(){ //求ab的最大公因数 int a,b,c; cin>>a>>b; do{ c=a%b; a=b; b=c; }while(b!=0); cout<<a; return 0; }