#include<cstdio>
int main(void) {
	long long int A, B, X, Y;
	scanf("%lld %lld", &A, &B);

	if (A == 1 || B == 1) { printf("1"); }
	else
	X = A + B;
	Y = A * B%X;
	while (X%Y != 0 && Y % X != 0) {
		if (X > Y) { X = X % Y; }
		else { Y = Y % X; }
	}

	if (X > Y) {printf("%lld",Y );}
	else { printf("%lld", X); }

	return 0;

}