#include<iostream>
using namespace std;
int main()
{
	int i,j,s;
	char c1[100],c2[100];
	//cin>>n;
	
	cin>>c1>>c2;

	while(1)
	{	cout<<endl;
		
		i=0;
		while(c1[i]!='\0')
			i++;
			
		j=0;
		while(c2[j]!='\0')
			j++;

		s=0;
	for(int x=0;x<i;x++)
		for(int y=0;y<j;y++)
			if(c1[x]==c2[y]&&c1[x]!='0'&&c2[y]!='0')
			{
				s++;
				for(int p=x+1;p<i;p++)
					if(c1[p]==c1[x])
						c1[p]='0';

			for(int q=y+1;q<j;q++)
					if(c2[q]==c2[y])
						c2[q]='0';

				c1[x]='0';
				c2[y]='0';
			}

		
	
				cout<<s<<endl;
				if(s==0)
				        break;
				else
		           cin>>c1>>c2;
		
	}
	return 0;
}