Day 19 and 20

2024/19/index.ts

@@ -0,0 +1,46 @@
+const fs = require('fs');
+
+const input = fs.readFileSync(__dirname + '/input.txt', 'utf8').split("\n");
+
+const towels: Array<string> = input[0].split(', ');
+
+const shortestTowel = Math.min(...towels.map((t: string) => t.length));
+const longestTowel = Math.max(...towels.map((t: string) => t.length));
+
+const designs = input.slice(2);
+
+let possible = 0;
+
+let permSum = 0;
+
+let patternMap: { [key: string]: number } = {};
+
+function canBeDone(pattern: string): number {
+    if (Object.hasOwn(patternMap, pattern)) {
+        return patternMap[pattern];
+    }
+    let perms = 0;
+    towels.forEach((t) => {
+        if (t === pattern) {
+            patternMap[pattern] = 1;
+            perms++;
+        } else if (pattern.startsWith(t)) {
+            const subPerms = canBeDone(pattern.substring(t.length));
+            perms += subPerms;
+        }
+    });
+    patternMap[pattern] = perms;
+    return perms;
+}
+
+designs.forEach((d: string, i: number)=> {
+    patternMap = {};
+    console.log(Math.floor(i / designs.length * 100));
+    const designPerms = canBeDone(d);
+    if (designPerms) {
+        possible++;
+        permSum += designPerms;
+    }
+});
+
+console.log(possible, permSum);