From d867d69f79173915aa4c0bbb64aac23a032e5d6f Mon Sep 17 00:00:00 2001
From: Alix von Schirp <github@avonschirp.bootmedia.de>
Date: Thu, 12 Dec 2024 00:43:26 +0100
Subject: [PATCH] Day 7

---
 Day 07/Part 1/index.ts | 27 +++++++++++++++++++++++++++
 Day 07/Part 2/index.ts | 28 ++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+)
 create mode 100644 Day 07/Part 1/index.ts
 create mode 100644 Day 07/Part 2/index.ts

diff --git a/Day 07/Part 1/index.ts b/Day 07/Part 1/index.ts
new file mode 100644
index 0000000..67c6026
--- /dev/null
+++ b/Day 07/Part 1/index.ts	
@@ -0,0 +1,27 @@
+import fs from 'node:fs';
+
+export default function runner(input: string) {
+  fs.readFile(`./${input}`, 'utf8', (err, data) => {
+    if (err) throw err;
+    let sum = 0;
+    data.split('\n').forEach(line => {
+      const [result, equators] = line.split(": ")
+      const factors = (equators??"").split(" ")
+      if(calculate(parseInt(result??""), factors.map(value => parseInt(value)))) sum += parseInt(result??"")
+    })
+    console.log(sum)
+  })
+}
+
+function calculate(result: number, factors: number[]): boolean{
+  return math(result, factors, 0, 0);
+}
+
+function math(result: number, factors: number[], index: number, runningTotal: number): boolean {
+  if(index === factors.length) return result === runningTotal;
+
+  const add = math(result, factors, index+1, runningTotal+(factors[index]??1))
+  const mult = math(result, factors, index+1, runningTotal*(factors[index]??1))
+
+  return add||mult;
+}
\ No newline at end of file
diff --git a/Day 07/Part 2/index.ts b/Day 07/Part 2/index.ts
new file mode 100644
index 0000000..c0e681b
--- /dev/null
+++ b/Day 07/Part 2/index.ts	
@@ -0,0 +1,28 @@
+import fs from 'node:fs';
+
+export default function runner(input: string) {
+  fs.readFile(`./${input}`, 'utf8', (err, data) => {
+    if (err) throw err;
+    let sum = 0;
+    data.split('\n').forEach(line => {
+      const [result, equators] = line.split(": ")
+      const factors = (equators??"").split(" ")
+      if(calculate(parseInt(result??""), factors.map(value => parseInt(value)))) sum += parseInt(result??"")
+    })
+    console.log(sum)
+  })
+}
+
+function calculate(result: number, factors: number[]): boolean{
+  return math(result, factors, 0, 0);
+}
+
+function math(result: number, factors: number[], index: number, runningTotal: number): boolean {
+  if(index === factors.length) return result === runningTotal;
+
+  const add = math(result, factors, index+1, runningTotal+(factors[index]??1))
+  const mult = math(result, factors, index+1, runningTotal*(factors[index]??1))
+  const concat = math(result, factors, index+1, parseInt(runningTotal + "" + (factors[index]??1)))
+
+  return add||mult||concat;
+}
\ No newline at end of file