#include<iostream>
using namespace std;
int main()
{
	int a,b,ci=0,aux,j,i;
	cin>>a>>b;
	while(a>b || a<0 || b<0)
		cin>>a>>b;
	for(i=a;i<b;i++)
	{
		for(j=i+1;j<=b;j++)
		{
			aux=i;
			while(aux>0)
			{
				if(aux%10==1)
					ci++;
				aux/=10;
			}
			aux=j;
			while(aux>0)
			{
				if(aux%10==1)
					ci++;
				aux/=10;
			}
			if(ci%2==0)
				cout<<i<<" "<<j<<endl;
			ci=0;
		}
	}
}