Add AoC Day 1 2024

adventofcode/2024/day/01/historian_hysteria.cpp

@@ -0,0 +1,24 @@
+#include <algorithm>
+#include <cstdio>
+#include <unordered_map>
+#include <utility>
+#include <vector>
+
+int main() {
+  std::pair<int, int> ans;
+  int left_number, right_number;
+  std::vector<int> left_numbers, right_numbers;
+  std::unordered_map<int, int> right_counter;
+  while(std::scanf("%d   %d\n", &left_number, &right_number) != EOF) {
+      left_numbers.push_back(left_number);
+      right_numbers.push_back(right_number);
+      right_counter[right_number] += 1;
+  }
+  std::ranges::sort(left_numbers);
+  std::ranges::sort(right_numbers);
+  for (int i = 0; i < std::ssize(left_numbers); i++) {
+      ans.first += std::abs(left_numbers[i] - right_numbers[i]);
+      ans.second += left_numbers[i] * (right_counter[left_numbers[i]]);
+  }
+  std::printf("Part one: %d\nPart two: %d\n", ans.first, ans.second);
+}