diff --git a/2019/24.cpp b/2019/24.cpp
index 21494cb..2640b7d 100644
--- a/2019/24.cpp
+++ b/2019/24.cpp
@@ -5,11 +5,14 @@
 #include <iterator>
 #include <map>
 #include <set>
+#include <sstream>
 #include <stdexcept>
 #include <string>
 #include <tuple>
 #include <vector>
 
+#include <doctest.h>
+
 #include <aocpp/Startup.hpp>
 #include <aocpp/Coord.hpp>
 #include <aocpp/Grid.hpp>
@@ -107,12 +110,12 @@ auto Part1(std::vector<Coord> const& bugs) -> std::uint32_t {
   return bio;
 }
 
-auto Part2(std::vector<Coord> const& bugs) {
+auto Part2(std::vector<Coord> const& bugs, int minutes) {
   std::vector<Neighbor2::C3> bugs2;
   for (auto const& [x,y] : bugs) {
     bugs2.push_back({{x-2,y-2},0});
   }
-  for (int i = 0; i < 200; i++) {
+  for (int i = 0; i < minutes; i++) {
     bugs2 = Step<Neighbor2::C3, Neighbor2>(bugs2);
   }
   return bugs2.size();
@@ -120,8 +123,20 @@ auto Part2(std::vector<Coord> const& bugs) {
 
 } // namespace
 
+TEST_SUITE("documented examples") {
+  TEST_CASE("part 1") {
+    std::istringstream in {"....#\n#..#.\n#..##\n..#..\n#....\n"};
+    REQUIRE(Part1(FindBugs(Grid::Parse(in))) == 2129920);
+  }
+  TEST_CASE("part 2") {
+    std::istringstream in {"....#\n#..#.\n#.?##\n..#..\n#....\n"};
+    REQUIRE(Part2(FindBugs(Grid::Parse(in)), 10) == 99);
+
+  }
+}
+
 auto main(int argc, char** argv) -> int {
   auto const bugs = FindBugs(Grid::Parse(Startup(argc, argv)));
   std::cout << "Part 1: " << Part1(bugs) << std::endl;
-  std::cout << "Part 2: " << Part2(std::move(bugs)) << std::endl;
+  std::cout << "Part 2: " << Part2(std::move(bugs), 200) << std::endl;
 }