2016 day14

1 files changed, 42 insertions, 23 deletions

diff --git a/src/2016/day14/aoc.cpp b/src/2016/day14/aoc.cpp
index dc49f69..364bb5e 100644
--- a/src/2016/day14/aoc.cpp
+++ b/src/2016/day14/aoc.cpp
@@ -5,8 +5,13 @@
 
 namespace aoc2016 {
 
-static std::map<char, std::set<size_t>> has3s;
-static std::map<char, std::set<size_t>> has5s;
+struct md5_property {
+  std::string md5;
+  char c = 0;
+};
+
+static std::vector<md5_property> md5s;
+static std::map<char, std::vector<size_t>> has5s;
 
 static bool is_equal(const char* p0, const char* p1) {
   while (p0 < p1) {
@@ -29,21 +34,21 @@ const char* has(const char* md5, int n) {
   return nullptr;
 }
 
-struct md5_property {
-  std::string md5;
-  char c3 = 0;
-  char c5 = 0;
-};
-
-static void insert(char c, size_t index, std::map<char, std::set<size_t>>& hs) {
-  auto p = hs.insert({c, {index}});
-  if (!p.second) {
-    p.first->second.insert(index);
+static bool in_range(char c, size_t l, size_t h) {
+  auto it = has5s.find(c);
+  if (it != has5s.end()) {
+    auto& v = it->second;
+    size_t ll = v[0];
+    size_t hh = v[v.size() - 1];
+    auto is_in = [l, h](size_t x) { return x >= l && x <= h; };
+    if (is_in(ll) || is_in(hh)) {
+      return true;
+    }
   }
+  return false;
 }
 
 md5_property md5(const char* secret, size_t index) {
-  static std::vector<md5_property> md5s;
   if (index >= md5s.size()) {
     char buf[128] = {0};
     int l = strlen(secret);
@@ -55,24 +60,38 @@ md5_property md5(const char* secret, size_t index) {
       md5s[i].md5 = std::string(md5sum(buf), 32);
       auto pc3 = has(md5s[i].md5.c_str(), 3);
       if (pc3 != nullptr) {
-        md5s[i].c3 = *pc3;
-        insert(*pc3, index, has3s);
-      }
-      auto pc5 = has(md5s[i].md5.c_str(), 5);
-      if (pc5 != nullptr) {
-        md5s[i].c5 = *pc5;
-        insert(*pc5, index, has5s);
+        md5s[i].c = *pc3;
+        auto pc5 = has(md5s[i].md5.c_str(), 5);
+        if (pc5 != nullptr) {
+          auto p = has5s.insert({*pc3, {index}});
+          if (!p.second) {
+            p.first->second.push_back(index);
+          }
+        }
       }
     }
   }
   return md5s[index];
 }
 
-void find_key(const char* secret, size_t index, int* count) {}
+size_t find_key(int* count, int max) {
+  size_t i{0};
+  while (*count < max && i < md5s.size()) {
+    auto& p = md5s[i];
+    if (p.c > 0 && in_range(p.c, i + 1, i + 1000)) {
+      *count += 1;
+    }
+    i++;
+  }
+  return i;
+}
 
 std::pair<int64_t, int64_t> day14(line_view) {
-  // md5("abc", 30000);
-  md5("jlmsuwbz", 30000);
+  md5("abc", 30000);
+  // md5("jlmsuwbz", 30000);
+  int count{0};
+  auto i = find_key(&count, 64);
+  printf("%zu\n", i);
   return {0, 0};
 }
 } // namespace aoc2016