#include<stdio.h>

int gcd(int,int);

int main()

{

int a,b;

scanf("%d%d",&a,&b);

printf("%d ",gcd(a,b));

return 0;

}

int gcd(int x,int y)

{

if (x!=y)

{

if(x>y)

{

x=x-y;

return gcd(x,y);

}

else

{

y=y-x;

return gcd(x,y);

}

}

else

return x;

}