aoc 2015 day 5

Author: jacobsandersen

src/main/java/dev/jacobandersen/codechallenges/challenge/adventofcode/year2015/Year2015.java

@@ -5,6 +5,7 @@
 import dev.jacobandersen.codechallenges.challenge.adventofcode.year2015.day2.Day2;
 import dev.jacobandersen.codechallenges.challenge.adventofcode.year2015.day3.Day3;
 import dev.jacobandersen.codechallenges.challenge.adventofcode.year2015.day4.Day4;
+import dev.jacobandersen.codechallenges.challenge.adventofcode.year2015.day5.Day5;
 
 import java.util.List;
 
@@ -14,7 +15,9 @@ public static List<Day> getDays() {
  new Day1(),
  new Day2(),
  new Day3(),
- new Day4()
+// Omitted normally, Day 4 is very slow due to MD5 bruteforce requirement
+// new Day4(),
+ new Day5()
  );
  }
 }

src/main/java/dev/jacobandersen/codechallenges/challenge/adventofcode/year2015/day5/Day5.java

@@ -0,0 +1,32 @@
+package dev.jacobandersen.codechallenges.challenge.adventofcode.year2015.day5;
+
+import dev.jacobandersen.codechallenges.challenge.adventofcode.Day;
+
+import java.util.regex.Pattern;
+import java.util.stream.Stream;
+
+public class Day5 extends Day {
+ public Day5() {
+ super(2015, 5, "Doesn't He Have Intern-Elves For This?");
+ }
+
+ private long countMatching(Stream<String> words, Pattern pattern) {
+ return words.filter(word -> pattern.matcher(word).matches()).count();
+ }
+
+ @Override
+ public String partOne() {
+ return String.valueOf(countMatching(
+ getInputLinesStreamNoBlanks(),
+ Pattern.compile("^(?=(.*[aeiou]){3,})(?=.*(.)\\2)(?!.*(?:ab|cd|pq|xy)).*$")
+ ));
+ }
+
+ @Override
+ public String partTwo() {
+ return String.valueOf(countMatching(
+ getInputLinesStreamNoBlanks(),
+ Pattern.compile("^(?=.*(..).*\\1)(?=.*(.).\\2).*$")
+ ));
+ }
+}