1 files changed, 32 insertions, 1 deletions
diff --git a/src/2018/day7/aoc.cpp b/src/2018/day7/aoc.cpp
index 6210814..354bfc8 100644
--- a/src/2018/day7/aoc.cpp
+++ b/src/2018/day7/aoc.cpp
@@ -2,8 +2,9 @@
 
 namespace aoc2018 {
 std::map<char, instruction*> instruction::instructions = {};
+size_t instruction::done_total = 0;
 
-void day7(line_view file, char sequence[]) {
+int day7(line_view file, char sequence[]) {
   per_line(file, [](line_view lv) {
     char p1 = *(lv.line + 5);
     char p2 = *(lv.line + 36);
@@ -20,6 +21,36 @@ void day7(line_view file, char sequence[]) {
     n->make_done();
     n = instruction::next();
   }
+
+  auto check = [](int s, instruction** w) {
+    if (*w != nullptr && (*w)->finished(s)) {
+      (*w)->make_done();
+      // std::cout << (*w)->label << " finishes at " << s << std::endl;
+      *w = nullptr;
+    }
+
+    if (*w == nullptr) {
+      instruction::next(w);
+      if (*w != nullptr) {
+        // std::cout << (*w)->label << " starts at " << s << std::endl;
+        (*w)->begin(s);
+      }
+    }
+  };
+
+  instruction::undo();
+  int second{0};
+  instruction* workers[5] = {nullptr, nullptr, nullptr, nullptr, nullptr};
+  // instruction* workers[2] = {nullptr, nullptr};
+  bool stop{false};
+  while (!stop) {
+    for (size_t i = 0; i < ARRAY_SIZE(workers) && !stop; i++) {
+      check(second, &workers[i]);
+    }
+    stop = instruction::all_done();
+    second += int(!stop);
+  }
+  return second;
 }
 
 } // namespace aoc2018