HackerrankPsAlgorithms0082.java

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.function.*;
import java.util.regex.*;
import java.util.stream.*;
import static java.util.stream.Collectors.joining;
import static java.util.stream.Collectors.toList;

public class HackerrankPsAlgorithms0082 {

	// Beautiful Binary String
	// https://www.hackerrank.com/challenges/beautiful-binary-string/problem?isFullScreen=true

	static class Result {

		public static int beautifulBinaryString(String b) {
			int count = 0;
			int i = 0;
			while (i < b.length() - 2) {
				if (b.charAt(i) == '0' && b.charAt(i + 1) == '1' && b.charAt(i + 2) == '0') {
					count++;
					i += 3;
				} else {
					i++;
				}
			}
			return count;
		}

	}

	public static void main(String[] args) throws IOException {
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        int n = Integer.parseInt(bufferedReader.readLine().trim());

        String b = bufferedReader.readLine();

        int result = Result.beautifulBinaryString(b);

        bufferedWriter.write(String.valueOf(result));
        bufferedWriter.newLine();

        bufferedReader.close();
        bufferedWriter.close();
    }

}