Mine

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;


public class Acm {

	public static int solve(String problem)
	{
		char[] prob = problem.toCharArray();
		List<Character> stacks = new ArrayList<Character>();
		int len = problem.length();
		for(int i=0; i<len; ++i) {
			boolean placed = false;
			for(int j=0; j<stacks.size() && !placed; ++j) {
				if(stacks.get(j) >= prob[i]) {
					stacks.set(j, prob[i]);
					placed = true;
				}
			}
			if(!placed) {
				stacks.add(prob[i]);
			}
		
		}
		return stacks.size();
	}
	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner s = new Scanner(System.in);
		String buffer = "";
		int i = 1;
		while(s.hasNext()) {
			buffer = s.next();
			if(buffer.equals("end")) { return; }
			System.out.println("Case " + i + ": " +  solve(buffer));
			++i;
		}

	}

}