2022 day16 part2

1 files changed, 44 insertions, 3 deletions

diff --git a/src/2022/day16/aoc.cpp b/src/2022/day16/aoc.cpp
index d381b6e..704d6e2 100644
--- a/src/2022/day16/aoc.cpp
+++ b/src/2022/day16/aoc.cpp
@@ -63,7 +63,7 @@ void update_total(int* total, std::map<valve*, int>& opened, int m) {
   *total = t;
 }
 
-bool is_open(valve* v, std::map<valve*, int>& opened) { return opened.find(v) != opened.end(); }
+bool is_open(valve* v, const std::map<valve*, int>& opened) { return opened.find(v) != opened.end(); }
 
 // m minutes left at v
 void flow(int m, valve* v, std::map<valve*, int> opened, int os, int total, int* max) {
@@ -111,6 +111,16 @@ struct valve_mm {
   }
 };
 
+std::vector<valve_m> cango(valve* v, int m, const std::map<valve*, int>& opened) {
+  std::vector<valve_m> t;
+  for (auto& vm : diagram[v]) {
+    if (!is_open(vm.v, opened) && m > vm.m) {
+      t.emplace_back(vm);
+    }
+  }
+  return t;
+}
+
 void flow(valve_m vs[2], std::map<valve_mm, int>& visited, std::map<valve*, int> opened, int os, int total, int* max) {
   for (auto i = 0; i < 2; i++) {
     update_total(&total, opened, vs[i].m);
@@ -151,8 +161,39 @@ void flow(valve_m vs[2], std::map<valve_mm, int>& visited, std::map<valve*, int>
         vs[1].m -= vs[1].m > 0 ? 1 : 0;
         flow(vs, visited, opened, os, total, max);
       } else {
-        // auto& ns0 = diagram[vs[0].v];
-        // auto& ns1 = diagram[vs[1].v];
+        auto ns0 = cango(vs[0].v, vs[0].m, opened);
+        auto ns1 = cango(vs[1].v, vs[1].m, opened);
+        if (ns0.size() == 0 && ns1.size() > 0) {
+          for (auto& n : ns1) {
+            vs[1].m -= n.m;
+            vs[1].v = n.v;
+            flow(vs, visited, opened, os, total, max);
+          }
+        }
+        if (ns0.size() > 0 && ns1.size() == 0) {
+          for (auto& n : ns0) {
+            vs[0].m -= n.m;
+            vs[0].v = n.v;
+            flow(vs, visited, opened, os, total, max);
+          }
+        }
+        if (ns0.size() > 0 && ns1.size() > 0) {
+          for (auto& n0 : ns0) {
+            for (auto& n1 : ns1) {
+              if (n0.v != n1.v) {
+                valve_m vx[2];
+                vx[0] = vs[0];
+                vx[1] = vs[1];
+
+                vx[0].m -= n0.m;
+                vx[0].v = n0.v;
+                vx[1].m -= n1.m;
+                vx[1].v = n1.v;
+                flow(vx, visited, opened, os, total, max);
+              }
+            }
+          }
+        }
       }
     }
   }