2017-02

2017/02.cpp

@@ -0,0 +1,75 @@
+#include <algorithm>
+#include <cstddef>
+#include <cstdint>
+#include <iostream>
+#include <iterator>
+#include <sstream>
+#include <string>
+#include <vector>
+
+#include <doctest.h>
+
+#include <aocpp/Startup.hpp>
+
+namespace {
+
+auto Omnibus(std::istream & in)
+-> std::pair<std::int64_t, std::int64_t>
+{
+  std::string line;
+  std::vector<std::int64_t> numbers;
+  std::int64_t p1{0}, p2{0};
+
+  while (std::getline(in, line)) {
+    numbers.clear();
+
+    std::istringstream inrow {std::move(line)};
+    std::copy(
+      std::istream_iterator<std::int64_t>{inrow},
+      std::istream_iterator<std::int64_t>{},
+      std::back_inserter(numbers));
+
+    std::sort(numbers.begin(), numbers.end());
+
+    p1 += numbers.back() - numbers.front();
+
+    auto n = numbers.size();
+    for (std::size_t i = 0; i < n; i++) {
+      for (std::size_t j = i+1; j < n; j++) {
+        if (numbers[j] % numbers[i] == 0) {
+          p2 += numbers[j] / numbers[i];
+          goto found;
+        }
+      }
+    }
+    found: {}
+  }
+  return {p1, p2};
+}
+
+} // namespace
+
+TEST_SUITE("2017-02 examples") {
+  TEST_CASE("part 1") {
+    std::istringstream in {
+      "5 1 9 5\n"
+      "7 5 3\n"
+      "2 4 6 8\n"};
+    CHECK(Omnibus(in).first == 18);
+  }
+  TEST_CASE("part 2") {
+    std::istringstream in {
+      "5 9 2 8\n"
+      "9 4 7 3\n"
+      "3 8 6 5\n"};
+    CHECK(Omnibus(in).second == 9);
+  }
+}
+
+auto main(int argc, char** argv) -> int {
+  auto in_ptr = aocpp::Startup(argc, argv);
+  auto & in = *in_ptr;
+  auto [p1,p2] = Omnibus(in);
+  std::cout << "Part 1: " << p1 << std::endl;
+  std::cout << "Part 2: " << p2 << std::endl;
+}

2017/CMakeLists.txt

@@ -1,3 +1,9 @@
+add_executable(2017_01 01.cpp)
+target_link_libraries(2017_01 aocpp)
+
+add_executable(2017_02 02.cpp)
+target_link_libraries(2017_02 aocpp)
+
 add_executable(2017_05 05.cpp)
 target_link_libraries(2017_05 aocpp)