HackerrankPsAlgorithms0015.java

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class HackerrankPsAlgorithms0015 {
	// Subarray Division
	// https://www.hackerrank.com/challenges/the-birthday-bar/problem?isFullScreen=true

	// --- You need to fill this method ---
	public static int birthday(List<Integer> s, int d, int m) {
		int count = 0;
		for (int i = 0; i <= s.size() - m; i++) {
			if (s.subList(i, i + m).stream().mapToInt(Integer::intValue).sum() == d) {
				count++;
			}
		}
		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());

		List<Integer> s = Stream.of(bufferedReader.readLine().replaceAll("\\s+$", "").split(" "))
				.map(Integer::parseInt)
				.collect(Collectors.toList());

		String[] firstMultipleInput = bufferedReader.readLine().replaceAll("\\s+$", "").split(" ");

		int d = Integer.parseInt(firstMultipleInput[0]);

		int m = Integer.parseInt(firstMultipleInput[1]);

		int result = birthday(s, d, m);

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

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

}