AOC4p1.java

package aoc;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class Day4 {

	static List<String> NEEDED = Arrays.asList( "byr", "iyr", "eyr", "hgt", "hcl", "ecl", "pid" );

	static Map<String, String> makePassport(String[] tokens)
	{
		return Stream
		 	.of(tokens)
		 	.map(t -> t.split(":"))
		 	.collect(Collectors.toMap(s->s[0], s->s[1]));
	}
	
	public static void main(String[] args) throws IOException 
	{
		String[] passports = Files.readString(Paths.get("input4.txt")).split("\n\n");
		
		var count = Stream.of(passports)
			.map(s -> s.split(" |\n"))
			.map(Day4::makePassport)
			.filter(p -> p.keySet().containsAll(NEEDED))
			.count();
		
		System.out.println(count);
	}

}