From 2f1784a972ea58152b34fda2ce61bfc71cd1a8b2 Mon Sep 17 00:00:00 2001
From: Thomas Schmucker <ts@its1.de>
Date: Sun, 22 Dec 2024 17:55:21 +0100
Subject: aoc 2024, day 22, part 1

---
 2024/src/day22.cpp | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)
 create mode 100644 2024/src/day22.cpp

diff --git a/2024/src/day22.cpp b/2024/src/day22.cpp
new file mode 100644
index 0000000..b103986
--- /dev/null
+++ b/2024/src/day22.cpp
@@ -0,0 +1,47 @@
+#include <cstdlib>
+#include <fstream>
+#include <iostream>
+#include <vector>
+using namespace std;
+
+vector<unsigned long>
+read_file(string_view filename)
+{
+	fstream               input{ filename };
+	vector<unsigned long> lines;
+
+	for ( unsigned long value{}; input >> value; ) {
+		lines.emplace_back(value);
+	}
+
+	return lines;
+}
+
+unsigned long
+step(unsigned long value)
+{
+	value = (value ^ (value * 64)) % 16777216;
+	value = (value ^ (value / 32)) % 16777216;
+	value = (value ^ (value * 2048)) % 16777216;
+	return value;
+}
+
+void
+part1(const vector<unsigned long>& values)
+{
+	unsigned long sum = 0;
+	for ( auto value: values ) {
+		for ( int i = 0; i != 2000; ++i ) {
+			value = step(value);
+		}
+		sum += value;
+	}
+	cout << sum << endl;
+}
+
+int
+main()
+{
+	auto data = read_file("data/day22.txt");
+	part1(data);
+}
-- 
cgit v1.3