import java.io.BufferedReader;
import java.io.InputStreamReader;
public class Main {
	public static void main (String[] args) throws Exception{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		final int ABC_SIZE = 26;
		int n = Integer.parseInt(br.readLine());
		for (int i = 0; i < n; i++) {
			int[] counters = new int[ABC_SIZE];
			String firstWord = br.readLine();
			for (int j = 0; j < firstWord.length(); j++) {
				counters[firstWord.charAt(j) - 'a']++;
			}
			String secondWord = br.readLine();
			for (int j = 0; j < secondWord.length(); j++) {
				counters[secondWord.charAt(j) - 'a']--;
			}
			int matchingLetters = 0;
			for (int k = 0; k < ABC_SIZE; k++) {
				matchingLetters += Math.abs(counters[k]);
			}
			System.out.println("Case #" + (i + 1) + ":  " + matchingLetters);
		}
		
	}
}