/*GCD最大公约数

* for循环法

* 辗转相除法method of successive division

*

*

* */

package Hello;

import java.util.Scanner;

public class GCD {

public static void main(String[] args) {

// TODO Auto-generated method stub

// MSD(null);

forloop(null);

}

public static void MSD(String[] args){

Scanner in = new Scanner(System.in);

int a = in.nextInt();

int b = in.nextInt();

int oa=a;

int ob=b;

while(b!=0)

{

int r=a%b;

System.out.println(a+","+b+","+r);

a=b;

b=r;

}

System.out.println(oa+"和"+ob+"的最大公约数是"+a);

}

public static void forloop(String[] args){

Scanner in = new Scanner(System.in);

int a = in.nextInt();

int b = in.nextInt();

int gcd=1;

for(int i=2;i<=a&&i<=b;i++)

{

if(a%i==0 & b%i ==0 )

{

gcd=i;

}

}

System.out.println(gcd);

}

}