import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = Integer.parseInt(sc.next());
		int b = Integer.parseInt(sc.next());
		int temp;

		// a ?????§???????????????
		if(a<b) {
			temp = a;
			a=b;
			b=temp;
		}
		
		while((a%b)!=0){
			temp = b;
			b=a%b;
			a=temp;
		}
		System.out.println(b);

	}

} import java.util.Scanner; Scanner java.util public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = Integer.parseInt(sc.next());
		int b = Integer.parseInt(sc.next());
		int temp;

		// a ?????§???????????????
		if(a<b) {
			temp = a;
			a=b;
			b=temp;
		}
		
		while((a%b)!=0){
			temp = b;
			b=a%b;
			a=temp;
		}
		System.out.println(b);

	}

} Main public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = Integer.parseInt(sc.next());
		int b = Integer.parseInt(sc.next());
		int temp;

		// a ?????§???????????????
		if(a<b) {
			temp = a;
			a=b;
			b=temp;
		}
		
		while((a%b)!=0){
			temp = b;
			b=a%b;
			a=temp;
		}
		System.out.println(b);

	} main {
		Scanner sc = new Scanner(System.in);
		int a = Integer.parseInt(sc.next());
		int b = Integer.parseInt(sc.next());
		int temp;

		// a ?????§???????????????
		if(a<b) {
			temp = a;
			a=b;
			b=temp;
		}
		
		while((a%b)!=0){
			temp = b;
			b=a%b;
			a=temp;
		}
		System.out.println(b);

	} Scanner sc = new Scanner(System.in); sc new Scanner(System.in) int a = Integer.parseInt(sc.next()); a Integer.parseInt(sc.next()) Integer.parseInt Integer sc.next() sc.next sc int b = Integer.parseInt(sc.next()); b Integer.parseInt(sc.next()) Integer.parseInt Integer sc.next() sc.next sc int temp; temp if(a<b) {
			temp = a;
			a=b;
			b=temp;
		} a<b a b {
			temp = a;
			a=b;
			b=temp;
		} temp = a temp a a=b a b b=temp b temp while((a%b)!=0){
			temp = b;
			b=a%b;
			a=temp;
		} (a%b)!=0 (a%b) a b 0 {
			temp = b;
			b=a%b;
			a=temp;
		} temp = b temp b b=a%b b a%b a b a=temp a temp System.out.println(b) System.out.println System.out System System.out b String[] args args public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = Integer.parseInt(sc.next());
		int b = Integer.parseInt(sc.next());
		int temp;

		// a ?????§???????????????
		if(a<b) {
			temp = a;
			a=b;
			b=temp;
		}
		
		while((a%b)!=0){
			temp = b;
			b=a%b;
			a=temp;
		}
		System.out.println(b);

	}

} public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = Integer.parseInt(sc.next());
		int b = Integer.parseInt(sc.next());
		int temp;

		// a ?????§???????????????
		if(a<b) {
			temp = a;
			a=b;
			b=temp;
		}
		
		while((a%b)!=0){
			temp = b;
			b=a%b;
			a=temp;
		}
		System.out.println(b);

	}

} Main
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int a = Integer.parseInt(sc.next());
		int b = Integer.parseInt(sc.next());
		int temp;

		// a ?????§???????????????
		if(a<b) {
			temp = a;
			a=b;
			b=temp;
		}
		
		while((a%b)!=0){
			temp = b;
			b=a%b;
			a=temp;
		}
		System.out.println(b);

	}

}