#include <stdio.h>

unsigned long long int gcd(unsigned long long int a,unsigned long long int b){
	unsigned long long int temp,r;
	while(1){
		if(a>b){
			temp=a;
			a=b;
			b=temp;
		}
		else{
			r=b%a;
			if(r==0)
				break;
			b=r;
		}
	}
	return a;
}

int main(){
	unsigned long long int A,B;
	scanf("%llu %llu",&A,&B);

	unsigned long long int a,gcd_aA,gcd_aB,eq_gcd,calc;
	a=A+B;

	gcd_aA=gcd(a,A);
	gcd_aB=gcd(a,B);
	eq_gcd=gcd(gcd_aA,gcd_aB);

	printf("%llu\n",eq_gcd);
	return 0;
}