2022 day23 elf

1 files changed, 100 insertions, 2 deletions

diff --git a/src/2022/day23/aoc.cpp b/src/2022/day23/aoc.cpp
index 825e67a..48a2099 100644
--- a/src/2022/day23/aoc.cpp
+++ b/src/2022/day23/aoc.cpp
@@ -1,9 +1,107 @@
 #include "aoc.h"
+#include <map>
+#include <set>
 
 namespace aoc2022 {
+typedef elf (*elf_move)(elf);
+typedef bool (*elf_predicate)(elf, const std::set<elf>&);
 
-std::pair<int, int> day23(line_view) {
-  return {0, 0};
+static elf nomove(elf e) { return e; }
+static elf north(elf e) { return elf{e.x, e.y - 1}; }
+static elf south(elf e) { return elf{e.x, e.y + 1}; }
+static elf west(elf e) { return elf{e.x - 1, e.y}; }
+static elf east(elf e) { return elf{e.x + 1, e.y}; }
+
+bool eight(elf e, const std::set<elf>& elves) {
+  elf es[8] = {
+      {e.x - 1, e.y - 1}, {e.x, e.y - 1},     {e.x + 1, e.y - 1}, {e.x - 1, e.y},
+      {e.x + 1, e.y},     {e.x - 1, e.y + 1}, {e.x, e.y + 1},     {e.x + 1, e.y + 1},
+  };
+  for (auto& e : es) {
+    if (elves.find(e) != elves.end()) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool north_three(elf e, const std::set<elf>& elves) {
+  elf es[3] = {
+      {e.x - 1, e.y - 1},
+      {e.x, e.y - 1},
+      {e.x + 1, e.y - 1},
+  };
+  for (auto& e : es) {
+    if (elves.find(e) != elves.end()) {
+      return false;
+    }
+  }
+  return true;
 }
+
+bool south_three(elf e, const std::set<elf>& elves) {
+  elf es[3] = {
+      {e.x - 1, e.y + 1},
+      {e.x, e.y + 1},
+      {e.x + 1, e.y + 1},
+  };
+  for (auto& e : es) {
+    if (elves.find(e) != elves.end()) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool west_three(elf e, const std::set<elf>& elves) {
+  elf es[3] = {
+      {e.x - 1, e.y - 1},
+      {e.x - 1, e.y},
+      {e.x - 1, e.y + 1},
+  };
+  for (auto& e : es) {
+    if (elves.find(e) != elves.end()) {
+      return false;
+    }
+  }
+  return true;
 }
 
+bool east_three(elf e, const std::set<elf>& elves) {
+  elf es[3] = {
+      {e.x + 1, e.y - 1},
+      {e.x + 1, e.y},
+      {e.x + 1, e.y + 1},
+  };
+  for (auto& e : es) {
+    if (elves.find(e) != elves.end()) {
+      return false;
+    }
+  }
+  return true;
+}
+
+struct elf_test {
+  elf_predicate p;
+  elf_move m;
+} moves[5] = {{eight, nomove}, {north_three, north}, {south_three, south}, {west_three, west}, {east_three, east}};
+
+std::pair<int, int> day23(line_view file) {
+  int height{0};
+  std::vector<elf> elfs;
+
+  per_line(file, [&height, &elfs](line_view lv) {
+    for (size_t i = 0; i < lv.length; i++) {
+      if (*(lv.line + i) == '#') {
+        elfs.emplace_back(elf{(int) i, height});
+      }
+    }
+    height++;
+    return true;
+  });
+
+  std::set<elf> elves{elfs.begin(), elfs.end()};
+
+  return {0, 0};
+}
+} // namespace aoc2022