From f0a86a6479480566df0c9bb3d1299e961963cd95 Mon Sep 17 00:00:00 2001
From: David Vereb <dev@eriestrayer.com>
Date: Thu, 5 Dec 2024 15:34:20 -0500
Subject: [PATCH] Day 5 Part 2.

---
 2024/5/main.cpp | 79 +++++++++++++++++++++++++++++++++----------------
 1 file changed, 54 insertions(+), 25 deletions(-)

diff --git a/2024/5/main.cpp b/2024/5/main.cpp
index c1accf9..687a849 100644
--- a/2024/5/main.cpp
+++ b/2024/5/main.cpp
@@ -7,6 +7,8 @@
 #include <string>
 #include <vector>
 
+bool IsBad(const std::vector<long> &row, const std::map<long, std::set<long>> &rules, size_t &bad_i);
+
 int main()
 {
 	const std::string filename = "data.txt";
@@ -94,34 +96,34 @@ int main()
 	// For each production run:
 	for(auto row : production)
 	{
-		std::set<long> already_passed;
-		bool bad = false;
-		// For each page number in that production run:
-		for(auto num : row)
-		{
-			// Check against all page numbers it shouldn't print after
-			for(auto before : rules[num])
-			{
-				// If found, it's a bad row!
-				if(std::find(already_passed.begin(), already_passed.end(), before) != already_passed.end())
-				{
-					bad = true;
-					break;
-				}
-			}
-
-			// Keep track of numbers we've looked at already:
-			already_passed.insert(num);
-		}
+		size_t bad_idx;
+		auto bad = IsBad(row, rules, bad_idx);
 
+		// Part 1:
 		if(!bad)
 			total += row[row.size() / 2];
-		// else
-		// 	std::cout << "not ";
-		// std::cout << "safe: ";
-		// for(auto num : row)
-		// 	std::cout << num << ",";
-		// std::cout << std::endl;
+		// Part 2:
+		else
+		{
+			std::vector<long> working;
+			for(auto n : row)
+				working.push_back(n);
+
+			while(IsBad(working, rules, bad_idx))
+			{
+				auto temp = working[bad_idx];
+				working.erase(working.begin() + bad_idx);
+				working.insert(working.begin(), temp);
+
+				// Debug Sort:
+				// std::cout << "Trying again: ";
+				// for(auto i : working)
+				// 	std::cout << i << ",";
+				// std::cout << std::endl;
+			}
+
+			total_pt2 += working[working.size() / 2];
+		}
 	}
 
 	std::cout << "    Total: " <<     total << std::endl;
@@ -129,3 +131,30 @@ int main()
 
 	return 0;
 }
+
+bool IsBad(const std::vector<long> &row, const std::map<long, std::set<long>> &rules, size_t &bad_i)
+{
+	std::set<long> already_passed;
+	bool bad = false;
+	// For each page number in that production run:
+	int i = 0;
+	for(auto num : row)
+	{
+		// Check against all page numbers it shouldn't print after
+		for(auto before : rules.at(num))
+		{
+			// If found, it's a bad row!
+			if(std::find(already_passed.begin(), already_passed.end(), before) != already_passed.end())
+			{
+				bad = true;
+				bad_i = i;
+				break;
+			}
+		}
+
+		// Keep track of numbers we've looked at already:
+		already_passed.insert(num);
+		++i;
+	}
+	return bad;
+}