2022-10

2022/10.cpp

@@ -0,0 +1,104 @@
+#include <cstdint>
+#include <iostream>
+#include <sstream>
+#include <stdexcept>
+#include <string>
+#include <vector>
+
+#include <doctest.h>
+
+#include <aocpp/Startup.hpp>
+
+namespace {
+
+auto Execute(std::istream & in) -> std::vector<std::int64_t>
+{
+  std::int64_t x {1}; // current register value (defined to start at 1)
+  std::int64_t d; // change in register value
+  std::string instruction;
+  std::vector<std::int64_t> snapshots;
+
+  while (in >> instruction) {
+    snapshots.push_back(x);
+    if ("addx" == instruction) {
+      snapshots.push_back(x);
+      if (!(in >> d)) {
+        throw std::runtime_error{"missing operand"};
+      }
+      x += d;
+    } else if ("noop" != instruction) {
+      throw std::runtime_error{"bad instruction"};
+    }
+  }
+  return snapshots;
+}
+
+auto Part1(std::vector<std::int64_t> const& snapshots) -> std::int64_t
+{
+  std::int64_t result {0};
+  for (auto i : {20,60,100,140,180,220}) {
+    result += i * snapshots[i-1];
+  }
+  return result;
+}
+
+auto Part2(std::vector<std::int64_t> const& snapshots, std::ostream & out) -> void
+{
+  auto constexpr rows {6};
+  auto constexpr cols {40};
+
+  if (snapshots.size() < rows * cols) {
+    throw std::runtime_error{"snapshots too short"};
+  }
+
+  auto cursor = snapshots.begin();
+  for (int r = 0; r < rows; r++) {
+    for (int c = 0; c < cols; c++) {
+      auto const d = *cursor++ - c;
+      out << (-1 <= d && d <= 1 ? "█" : "░");
+    }
+    out << std::endl;
+  }
+}
+
+} // namespace
+
+TEST_SUITE("2022-10 examples") {
+  TEST_CASE("example") {
+    std::istringstream in {
+      "addx 15\naddx -11\naddx 6\naddx -3\naddx 5\naddx -1\naddx -8\naddx 13\naddx 4\nnoop\n"
+      "addx -1\naddx 5\naddx -1\naddx 5\naddx -1\naddx 5\naddx -1\naddx 5\naddx -1\naddx -35\n"
+      "addx 1\naddx 24\naddx -19\naddx 1\naddx 16\naddx -11\nnoop\nnoop\naddx 21\naddx -15\n"
+      "noop\nnoop\naddx -3\naddx 9\naddx 1\naddx -3\naddx 8\naddx 1\naddx 5\nnoop\nnoop\nnoop\n"
+      "noop\nnoop\naddx -36\nnoop\naddx 1\naddx 7\nnoop\nnoop\nnoop\naddx 2\naddx 6\nnoop\n"
+      "noop\nnoop\nnoop\nnoop\naddx 1\nnoop\nnoop\naddx 7\naddx 1\nnoop\naddx -13\naddx 13\n"
+      "addx 7\nnoop\naddx 1\naddx -33\nnoop\nnoop\nnoop\naddx 2\nnoop\nnoop\nnoop\naddx 8\nnoop\n"
+      "addx -1\naddx 2\naddx 1\nnoop\naddx 17\naddx -9\naddx 1\naddx 1\naddx -3\naddx 11\nnoop\n"
+      "noop\naddx 1\nnoop\naddx 1\nnoop\nnoop\naddx -13\naddx -19\naddx 1\naddx 3\naddx 26\n"
+      "addx -30\naddx 12\naddx -1\naddx 3\naddx 1\nnoop\nnoop\nnoop\naddx -9\naddx 18\naddx 1\n"
+      "addx 2\nnoop\nnoop\naddx 9\nnoop\nnoop\nnoop\naddx -1\naddx 2\naddx -37\naddx 1\naddx 3\n"
+      "noop\naddx 15\naddx -21\naddx 22\naddx -6\naddx 1\nnoop\naddx 2\naddx 1\nnoop\naddx -10\n"
+      "noop\nnoop\naddx 20\naddx 1\naddx 2\naddx 2\naddx -6\naddx -11\nnoop\nnoop\nnoop\n"
+    };
+    
+    auto snapshots = Execute(in);
+    CHECK(13140 == Part1(snapshots));
+    std::ostringstream out;
+    Part2(snapshots, out);
+    CHECK(out.str() ==
+      "██░░██░░██░░██░░██░░██░░██░░██░░██░░██░░\n"
+      "███░░░███░░░███░░░███░░░███░░░███░░░███░\n"
+      "████░░░░████░░░░████░░░░████░░░░████░░░░\n"
+      "█████░░░░░█████░░░░░█████░░░░░█████░░░░░\n"
+      "██████░░░░░░██████░░░░░░██████░░░░░░████\n"
+      "███████░░░░░░░███████░░░░░░░███████░░░░░\n"
+    );
+  }
+}
+
+auto main(int argc, char** argv) -> int
+{
+  auto snapshots = Execute(*aocpp::Startup(argc, argv));
+  std::cout << "Part 1: " << Part1(snapshots) << std::endl;
+  Part2(snapshots, std::cout << "Part 2:\n");
+}

2022/CMakeLists.txt

@@ -13,6 +13,9 @@ target_link_libraries(2022_08 aocpp)
 add_executable(2022_09 09.cpp)
 target_link_libraries(2022_09 aocpp)
 
+add_executable(2022_10 10.cpp)
+target_link_libraries(2022_10 aocpp)
+
 add_executable(2022_12 12.cpp)
 target_link_libraries(2022_12 aocpp)