first commit

2024/day01/part1.cc

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+#include <vector>
+#include <iostream>
+#include <ranges>
+#include <cstdlib>
+#include <cmath>
+#include <cassert>
+#include <algorithm>
+
+int main() {
+  std::vector<int> left_list, right_list;
+  int left, right;
+  while (std::cin >> left >> right) {
+    left_list.emplace_back(left);
+    right_list.emplace_back(right);
+  }
+  std::sort(left_list.begin(), left_list.end());
+  std::sort(right_list.begin(), right_list.end());
+  assert(left_list.size() == right_list.size());
+  int diff = 0;
+  for(auto [left_elem, right_elem] : std::views::zip(left_list, right_list)) {
+    diff += std::abs(left_elem - right_elem);
+  }
+  std::cout << diff << std::endl;
+  return EXIT_SUCCESS;
+}

2024/day01/part2.cc

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+#include <vector>
+#include <unordered_map>
+#include <iostream>
+#include <ranges>
+#include <cstdlib>
+#include <cmath>
+
+int main() {
+  std::vector<int> left_list;
+  std::unordered_map<int, int> right_list;
+  int left, right;
+  while (std::cin >> left >> right) {
+    left_list.emplace_back(left);
+    right_list[right]++;
+  }
+  int score = 0;
+  for(auto left_elem : left_list) {
+    score += left_elem * right_list[left_elem];
+  }
+  std::cout << score << std::endl;
+  return EXIT_SUCCESS;
+}