feat: solve day 19 part 2

Flashky · Dec 19, 2024 · cccb264 · cccb264
1 parent 63a1576
commit cccb264
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Showing 3 changed files with 24 additions and 9 deletions.
diff --git a/src/main/java/com/adventofcode/flashk/day19/LinenLayout2.java b/src/main/java/com/adventofcode/flashk/day19/LinenLayout2.java
@@ -12,7 +12,7 @@ public class LinenLayout2 {
     private List<String> patterns;
     private List<String> designs;
 
-    private Map<String,Boolean> memo = new HashMap<>();
+    private Map<MemoState,Long> memo = new HashMap<>();
 
     public LinenLayout2(List<String> inputs) {
         patterns = Arrays.stream(inputs.getFirst().replace(StringUtils.SPACE, StringUtils.EMPTY).split(","))
@@ -23,29 +23,41 @@ public LinenLayout2(List<String> inputs) {
         designs = inputs;
     }
 
-    public int solveB() {
-        int result = 0;
+    public long solveB() {
+        long result = 0;
         for(String design : designs) {
             result += count(design, StringUtils.EMPTY);
+            memo.clear();
         }
         return result;
     }
 
-    private int count(String design, String pattern){
+    private long count(String design, String pattern){
 
         if(design.equals(pattern)) {
-            return 1;
+            return 1L;
         }
 
         if(!design.startsWith(pattern)) {
             return 0;
         }
 
-        int count = 0;
+        long count = 0;
         String rightSide = design.replaceFirst(pattern, StringUtils.EMPTY);
 
         for(String newPattern : patterns) {
-            count += count(rightSide, newPattern);
+
+            MemoState newState = new MemoState(rightSide, newPattern);
+
+            long partialCount;
+            if(memo.containsKey(newState)) {
+                partialCount = memo.get(newState);
+            } else {
+                partialCount = count(rightSide, newPattern);
+                memo.put(new MemoState(rightSide, newPattern), partialCount);
+            }
+
+            count += partialCount;
         }
 
         return count;

diff --git a/src/main/java/com/adventofcode/flashk/day19/MemoState.java b/src/main/java/com/adventofcode/flashk/day19/MemoState.java
@@ -0,0 +1,4 @@
+package com.adventofcode.flashk.day19;
+
+public record MemoState(String design, String pattern) {
+}
diff --git a/src/test/java/com/adventofcode/flashk/day19/Day19Test.java b/src/test/java/com/adventofcode/flashk/day19/Day19Test.java
@@ -79,8 +79,7 @@ public void testSolvePart2Input() {
 		// Read input file
 		List<String> inputs = Input.readStringLines(INPUT_FOLDER, TestFilename.INPUT_FILE);
 		LinenLayout2 linenLayout = new LinenLayout2(inputs);
-		System.out.println("Solution: "+linenLayout.solveB());
-		assertEquals(0L,0L);
+		assertEquals(619970556776002L,linenLayout.solveB());
 
 	}