1 files changed, 36 insertions, 7 deletions

diff --git a/src/2022/day13/aoc.h b/src/2022/day13/aoc.h
index d0749fc..7999e25 100644
--- a/src/2022/day13/aoc.h
+++ b/src/2022/day13/aoc.h
@@ -11,13 +11,13 @@ struct packet {
 
   struct componet {
     componet_t t;
-    int v;
-    packet *p;
+    int v = 0;
+    packet *p = nullptr;
   };
 
   std::vector<componet*> ps;
 
-  void get_number(const char** p, int* d) {
+  static void get_number(const char** p, int* d) {
     const char* p0 = *p;
     while (*p0 >= '0' && *p0 <= '9') {
       *d = 10 * (*d) + *p0 - '0';
@@ -26,14 +26,14 @@ struct packet {
     *p = p0;
   }
 
-  void load(const char** p, packet** pp) {
+  static void load(const char** p, packet** pp) {
     const char* p0 = *p;
     while (*p0 != '\n') {
+      p0++;
       if (*p0 >= '0' && *p0 <= '9') {
         componet* c = new componet;
         c->t = is_int;
         get_number(&p0, &c->v);
-        c->p = nullptr;
         (*pp)->ps.push_back(c);
       }
       else if (*p0 == '[') {
@@ -47,12 +47,41 @@ struct packet {
         *p = p0;
         return;
       } 
-      p0++;
     }
   }
 
+  static packet* make_packet(int v) {
+    componet* c = new componet;
+    c->p = nullptr;
+    c->t = is_int;
+    c->v = v;
+    packet* p = new packet;
+    p->ps.push_back(c);
+    return p;
+  }
+
   friend bool operator<(const packet& p1, const packet& p2) {
-    return true;
+    for (size_t i = 0; i < p1.ps.size() && i < p2.ps.size(); i++) {
+      componet* c1 = p1.ps[i];
+      componet* c2 = p2.ps[i];
+      if (c1->t == is_int && c2->t == is_int) {
+        // printf("compare %d %d\n", c1->v, c2->v);
+        if (c1->v < c2->v) return true;
+        if (c1->v > c2->v) return false;
+      }
+      if (c1->t == is_int && c2->t == is_list) {
+        packet *p = make_packet(c1->v);
+        return *p < *(c2->p);
+      }
+      if (c1->t == is_list && c2->t == is_int) {
+        packet *p = make_packet(c2->v);
+        return *(c1->p) < *(p);
+      }
+      if (c1->t == is_list && c2->t == is_list) {
+        return *(c1->p) < *(c2->p);
+      }
+    }
+    return p1.ps.size() <= p2.ps.size();
   }
 };