# include<stdio.h>
# include<string.h>
main()
{
	char arr1[30];
	char arr2[30];
	scanf("%s",arr1);
	scanf("%s",arr2);
	int i,j,l1,l2;
	l1=strlen(arr1);
	l2=strlen(arr2);
	int min,max;
	if(l1<=l2)
	{
	 min=l1;
	 max=l2;
	 for(i=0;i<min;i++)
	 {
	 for(j=0;j<max;j++)
	 {
	  if(arr1[i]==arr2[j])
	  printf("%c",arr1[i]);
	 }
	 }
	}
	else
	{
          min=l2;max=l1;
	  for(i=0;i<min;i++)
	  {
	   for(j=0;j<max;j++)
	   {
	    if(arr2[i]==arr1[j])
	    printf("%c",arr2[i]);
	    }
	   }
	  }
	  

}