From f0159b7d36e2c81182f2d047a34bf883394894db Mon Sep 17 00:00:00 2001
From: Sebastiano Tronto <sebastiano@tronto.net>
Date: Wed, 25 Dec 2024 06:55:22 +0100
Subject: Day 25 2024

---
 2024/25/Makefile   | 11 +++++++++++
 2024/25/day25a.cpp | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+)
 create mode 100644 2024/25/Makefile
 create mode 100644 2024/25/day25a.cpp

diff --git a/2024/25/Makefile b/2024/25/Makefile
new file mode 100644
index 0000000..67dcdd1
--- /dev/null
+++ b/2024/25/Makefile
@@ -0,0 +1,11 @@
+CC=g++ -std=c++20 -g -Wall
+
+a:
+	${CC} -o a.out day25a.cpp
+	./a.out
+
+b:
+	${CC} -o b.out day25b.cpp
+	./b.out
+
+.PHONY: a b
diff --git a/2024/25/day25a.cpp b/2024/25/day25a.cpp
new file mode 100644
index 0000000..22d8c15
--- /dev/null
+++ b/2024/25/day25a.cpp
@@ -0,0 +1,55 @@
+#include <algorithm>
+#include <cstdint>
+#include <iostream>
+#include <map>
+#include <queue>
+#include <ranges>
+#include <set>
+#include <sstream>
+#include <string>
+#include <string_view>
+#include <vector>
+using namespace std;
+
+class KeyLock {
+public:
+	KeyLock() { fill(a, a+5, 0); }
+
+	void addrow(const string& s) {
+		for (int i = 0; i < 5; i++)
+			a[i] += s[i] == '#';
+	}
+
+	bool operator&(const KeyLock& other) const {
+		for (int i = 0; i < 5; i++)
+			if (a[i] + other.a[i] > 5)
+				return false;
+		return true;
+	}
+private:
+	int a[5];
+};
+
+int main() {
+	vector<KeyLock> keys, locks;
+	string line;
+	while (getline(cin, line)) {
+		KeyLock k;
+		bool key = line[0] == '.';
+		for (int i = 0; i < 5; i++) {
+			getline(cin, line);
+			k.addrow(line);
+		}
+		if (key) keys.push_back(k);
+		else locks.push_back(k);
+		getline(cin, line);
+		getline(cin, line);
+	}
+
+	int tot = 0;
+	for (auto k : keys)
+		for (auto l : locks)
+			tot += (k & l) ? 1 : 0;
+	cout << tot << endl;
+	return 0;
+}
-- 
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