From 7949fb91c550a7a39093b7cc58ef73d2e0cfffb1 Mon Sep 17 00:00:00 2001
From: Mars Ultor <krishna@ayyalasomayajula.net>
Date: Mon, 1 Dec 2025 21:13:47 -0600
Subject: [PATCH] day 1 done

---
 src/day-1-solution.cpp | 79 +++++++++++++++++++++++++++++++++++++++---
 1 file changed, 74 insertions(+), 5 deletions(-)

diff --git a/src/day-1-solution.cpp b/src/day-1-solution.cpp
index 1117a34..11ec6b3 100644
--- a/src/day-1-solution.cpp
+++ b/src/day-1-solution.cpp
@@ -1,4 +1,14 @@
+#include "spdlog/common.h"
+#include "spdlog/spdlog.h"
+#include <algorithm>
+#include <charconv>
+#include <cstdint>
 #include <expected>
+#include <fstream>
+#include <ios>
+#include <pthread.h>
+#include <string>
+#include <sys/types.h>
 #include <utility>
 #include <vector>
 
@@ -6,13 +16,72 @@ enum Direction {
  LEFT=-1, RIGHT=1 
 };
 
-int main (int argc, char *argv[]) {
+uint_fast32_t solution_part_one(std::vector<std::pair<Direction, int>> moves){
+  constexpr thread_local static int default_start = int {50};
+
+  int position = {default_start};
+  uint_fast32_t count_zero_cross = {0};
+  for (std::vector<std::pair<Direction, int>>::iterator i = moves.begin(); i<moves.end(); i++) {
+    position+=(i->first) * i->second;
+    position %=100;
+    position = position<0 ? position +100 : position;
+    spdlog::debug("Current position: {}", position);
+    if(position==0)++count_zero_cross;
+  }
   
+  return count_zero_cross;
+}
+
+
+uint_fast32_t solution_part_two(std::vector<std::pair<Direction, int>> moves){
+  constexpr thread_local static int default_start = int {50};
+
+  int position = {default_start};
+  uint_fast32_t count_zero_cross = {0};
+  for (std::vector<std::pair<Direction, int>>::iterator i = moves.begin(); i<moves.end(); i++) {
+    for (int steps =0; steps<i->second; steps++) {
+      position = (position + i->first + 100) % 100;
+      if (position==0) count_zero_cross++;
+    }
+    spdlog::debug("Current position: {}", position); 
+  }
+  
+  return count_zero_cross;
+}
+
+
+int main (int argc, char *argv[]) {
+  spdlog::set_level(spdlog::level::level_enum::info);
+  std::vector<std::pair<Direction, int>> moves_to_submit = std::vector<std::pair<Direction, int>> {};
+  std::ifstream input = std::ifstream{"testcases/day-1.in", std::ios::ios_base::binary};
+
+  {
+    std::string current_line = std::string {};
+    while (std::getline(input, current_line)) {
+      char direction_char = current_line.at(0);
+       int magnitude = int {};
+     std::from_chars(current_line.data()+1, current_line.data()+current_line.size(), magnitude);
+      Direction chosen;
+      switch (direction_char) {
+        case 'R':
+          chosen = Direction::RIGHT;
+          break;
+        case 'L':
+          chosen = Direction::LEFT;
+          break;
+        default:
+          spdlog::critical("parsing error done on line: {}", current_line);
+      }
+      moves_to_submit.push_back(std::make_pair(chosen, magnitude));
+      spdlog::debug("added chosen: {}, magnitude: {}", static_cast<int>(chosen), magnitude);
+    }
+  }
+
+  uint_fast32_t part_one_solution = solution_part_one(moves_to_submit); 
+  spdlog::info("Part One Solution {}", part_one_solution);
+  uint_fast32_t part_two_solution = solution_part_two(moves_to_submit);
+  spdlog::info("Part Two Solution {}", part_two_solution);
   return 0;
 }
 
-int solution(std::vector<std::pair<Direction, int>> moves){
-  constexpr thread_local static int default_start = int {50};
 
-  return default_start;
-}