a.java

import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.io.*;
import java.math.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
public class A {
	static BufferedReader br;
	static StringTokenizer st;
	static PrintWriter pw;
	
	public static void main(String[] args) throws Exception {
		br = new BufferedReader(new InputStreamReader(System.in));
		pw = new PrintWriter(new BufferedWriter(new FileWriter("a.out")));
		final int MAX_CASES = readInt();
		for(int casenum = 1; casenum <= MAX_CASES; casenum++) {
			pw.printf("Case #%d: ", casenum);
			int n = readInt();
			int[] counts = new int[n+1];
			String s = nextToken();
			for(int i = 0; i < s.length(); i++) {
				counts[i] = s.charAt(i) - '0';
			}
			int ret = 0;
			int curr = 0;
			for(int i = 0; i < counts.length; i++) {
				if(curr < i) {
					ret += i - curr;
					curr = i;
				}
				curr += counts[i];
			}
			pw.println(ret);
		}
		pw.close();
	}

	public static int readInt() {
		return Integer.parseInt(nextToken());
	}

	public static long readLong() {
		return Long.parseLong(nextToken());
	}

	public static double readDouble() {
		return Double.parseDouble(nextToken());
	}

	public static String nextToken() {
		while(st == null || !st.hasMoreTokens())	{
			try {
				if(!br.ready())	{
					pw.close();
					System.exit(0);
				}
				st = new StringTokenizer(br.readLine());
			}
			catch(IOException e) {
				System.err.println(e);
				System.exit(1);
			}
		}
		return st.nextToken();
	}

	public static String readLine()	{
		st = null;
		try {
			return br.readLine();
		}
		catch(IOException e) {
			System.err.println(e);
			System.exit(1);
			return null;
		}
	}

}