From fe67687bf7312cec847a8d8bfcb3f96f2e14bcb3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20M=C3=BCller?= <stefan.mueller@aksdb.de>
Date: Mon, 2 Dec 2024 14:57:18 +0100
Subject: [PATCH] Add solution for "Day 2: Red-Nosed Reports", part 1

---
 AdventOfCode2024/AdventOfCode2024.vcxproj     |  2 +
 .../AdventOfCode2024.vcxproj.filters          |  6 ++
 AdventOfCode2024/Program.cpp                  |  2 +
 AdventOfCode2024/RedNosedReports.cpp          | 69 +++++++++++++++++++
 AdventOfCode2024/RedNosedReports.h            | 30 ++++++++
 5 files changed, 109 insertions(+)
 create mode 100644 AdventOfCode2024/RedNosedReports.cpp
 create mode 100644 AdventOfCode2024/RedNosedReports.h

diff --git a/AdventOfCode2024/AdventOfCode2024.vcxproj b/AdventOfCode2024/AdventOfCode2024.vcxproj
index 7af98e5..7b8c698 100644
--- a/AdventOfCode2024/AdventOfCode2024.vcxproj
+++ b/AdventOfCode2024/AdventOfCode2024.vcxproj
@@ -131,12 +131,14 @@
     <ClCompile Include="AdventOfCode2024.cpp" />
     <ClCompile Include="HistorianHysteria.cpp" />
     <ClCompile Include="Program.cpp" />
+    <ClCompile Include="RedNosedReports.cpp" />
     <ClCompile Include="Solver.cpp" />
     <ClCompile Include="SolverEngine.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="HistorianHysteria.h" />
     <ClInclude Include="Program.h" />
+    <ClInclude Include="RedNosedReports.h" />
     <ClInclude Include="Solver.h" />
     <ClInclude Include="SolverEngine.h" />
   </ItemGroup>
diff --git a/AdventOfCode2024/AdventOfCode2024.vcxproj.filters b/AdventOfCode2024/AdventOfCode2024.vcxproj.filters
index d9e4eb4..399c5a9 100644
--- a/AdventOfCode2024/AdventOfCode2024.vcxproj.filters
+++ b/AdventOfCode2024/AdventOfCode2024.vcxproj.filters
@@ -30,6 +30,9 @@
     <ClCompile Include="HistorianHysteria.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="RedNosedReports.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="SolverEngine.h">
@@ -44,5 +47,8 @@
     <ClInclude Include="HistorianHysteria.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="RedNosedReports.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>
\ No newline at end of file
diff --git a/AdventOfCode2024/Program.cpp b/AdventOfCode2024/Program.cpp
index 70f0ece..28ec101 100644
--- a/AdventOfCode2024/Program.cpp
+++ b/AdventOfCode2024/Program.cpp
@@ -20,6 +20,7 @@
 #include "SolverEngine.h"
 
 #include "HistorianHysteria.h"
+#include "RedNosedReports.h"
 
 void Program::run()
 {
@@ -31,6 +32,7 @@ void Program::runSolvers()
 {
     SolverEngine solverEngine{ getInputPaths() };
     solverEngine.run(*std::make_unique<HistorianHysteria>());
+    solverEngine.run(*std::make_unique<RedNosedReports>());
 }
 
 std::vector<std::string> Program::getInputPaths() const
diff --git a/AdventOfCode2024/RedNosedReports.cpp b/AdventOfCode2024/RedNosedReports.cpp
new file mode 100644
index 0000000..7587854
--- /dev/null
+++ b/AdventOfCode2024/RedNosedReports.cpp
@@ -0,0 +1,69 @@
+// Solutions to the Advent Of Code 2024.
+// Copyright (C) 2024  Stefan Müller
+//
+// This program is free software: you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free Software
+// Foundation, either version 3 of the License, or (at your option) any later
+// version.
+//
+// This program is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with
+// this program.  If not, see <http://www.gnu.org/licenses/>.
+
+#include <iostream>
+#include <sstream>
+
+#include "RedNosedReports.h"
+#include <iomanip>
+
+std::string RedNosedReports::getPuzzleName() const
+{
+    return "Day 2: Red-Nosed Reports";
+}
+
+std::string RedNosedReports::getInputFileName() const
+{
+    return "red-nosed_reports.txt";
+}
+
+void RedNosedReports::processDataLine(const std::string& line)
+{
+    auto isSafe{ true };
+    auto slope{ Slope::Unknown };
+
+    std::stringstream stream{ line };
+    std::string token;
+    std::getline(stream, token, ' ');
+    auto prev{ std::stoi(token) };
+
+    while (isSafe && std::getline(stream, token, ' '))
+    {
+        auto next{ std::stoi(token) };
+        auto delta{ next - prev };
+        if (delta == 0 || delta > 3 || delta < -3
+            || (delta > 0 && slope == Slope::Decreasing)
+            || (delta < 0 && slope == Slope::Increasing))
+        {
+            isSafe = false;
+        }
+        else
+        {
+            prev = next;
+            if (slope == Slope::Unknown)
+            {
+                slope = delta > 0 ? Slope::Increasing : Slope::Decreasing;
+            }
+        }
+    }
+    if (isSafe)
+    {
+        part1++;
+    }
+}
+
+void RedNosedReports::finish()
+{
+}
diff --git a/AdventOfCode2024/RedNosedReports.h b/AdventOfCode2024/RedNosedReports.h
new file mode 100644
index 0000000..ea8cd0c
--- /dev/null
+++ b/AdventOfCode2024/RedNosedReports.h
@@ -0,0 +1,30 @@
+// Solutions to the Advent Of Code 2024.
+// Copyright (C) 2024  Stefan Müller
+//
+// This program is free software: you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free Software
+// Foundation, either version 3 of the License, or (at your option) any later
+// version.
+//
+// This program is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along with
+// this program.  If not, see <http://www.gnu.org/licenses/>.
+
+#pragma once
+
+#include "Solver.h"
+
+class RedNosedReports :
+    public Solver
+{
+public:
+    std::string getPuzzleName() const override;
+    std::string getInputFileName() const override;
+    void processDataLine(const std::string& line) override;
+    void finish() override;
+};
+
+enum class Slope { Unknown, Increasing, Decreasing };