/*
 *  gcd.c
 *  
 *
 *  Created by Andrew on 2/5/11.
 *  Copyright 2011 UvA. All rights reserved.
 *
 */

extern void printInt( int val);
extern void printFloat( float val);

extern int scanInt( );
extern float scanFloat( );

extern void printSpaces( int num);
extern void printNewlines( int num);


int gcd_cal(int min,int max)
{
	int media;
	if(min>max)
	{
		media=min;
		min=max;
		max=media;
	}
	
	while(min>0)
	{
		max=max-min;
		if(min>max)
		{
			media=min;
			min=max;
			max=media;
		}
	}
	return max;
	
}

export int main()
{
	int max=scanInt();
	int min=scanInt();
	
	int gcd=0;
	
	if(max==0||min==0)
		printInt(gcd);
	else
	{
		gcd=gcd_cal(max,min);	
		printInt(gcd);
	}	
	printNewlines(1);
	return 0;
}