aoc(2307): Camel Cards

1 files changed, 113 insertions, 0 deletions

diff --git a/2023/07/src/part2.cpp b/2023/07/src/part2.cpp
new file mode 100644
index 0000000..239df11
--- /dev/null
+++ b/2023/07/src/part2.cpp
@@ -0,0 +1,113 @@
+#include <algorithm>
+#include <array>
+#include <fstream>
+#include <iostream>
+#include <set>
+#include <sstream>
+#include <string>
+
+class Hand
+{
+    static constexpr int HAND{ 5 };
+
+    int bet_;
+    int score_{};
+    std::array<char,HAND> cards_;
+
+public:
+    Hand(const std::string& cards, int bet) : bet_{ bet }
+    {
+        for (int c = 0; c < HAND; ++c)
+        {
+            switch (cards[c])
+            {
+                case 'A':
+                    cards_[c] = 12;
+                    break;
+                case 'K':
+                    cards_[c] = 11;
+                    break;
+                case 'Q':
+                    cards_[c] = 10;
+                    break;
+                case 'J':
+                    cards_[c] = 0;
+                    break;
+                case 'T':
+                    cards_[c] = 9;
+                    break;
+                default:
+                    cards_[c] = cards[c] - '1';
+            }
+        }
+
+        std::array<int,13> mult{};
+        std::for_each(cards_.begin(), cards_.end(), [&mult](int c) { ++mult[c]; });
+        std::for_each(mult.begin() + 1, mult.end(), [this](int c) {
+            switch (c)
+            {
+                case 2:
+                    this->score_ += 1;
+                    break;
+                case 3:
+                    this->score_ += 3;
+                    break;
+                case 4:
+                    this->score_ += 5;
+                    break;
+                case 5:
+                    this->score_ += 6;
+                    break;
+            }
+        });
+        for (int j = 1; j <= mult[0] and j < HAND; ++j)
+        {
+            score_ += (1 <= score_ and score_ < 4) ? 2 : 1;
+        }
+    }
+
+    inline int bet() const
+    {
+        return bet_;
+    }
+
+    bool operator<(const Hand& that) const
+    {
+        return this->score_ < that.score_ or
+               (this->score_ == that.score_ and this->cards_ < that.cards_);
+    }
+
+    static Hand from_string(const std::string& str)
+    {
+        int bet;
+        std::string hand;
+        std::istringstream{ str } >> hand >> bet;
+        return { hand, bet };
+    }
+};
+
+int main(void)
+{
+    int answer{};
+    std::multiset<Hand> hands;
+
+    std::ifstream input{ "resources/input.txt" };
+    if (input.is_open())
+    {
+        std::string line;
+        while (not std::getline(input,line).eof())
+        {
+            hands.insert(Hand::from_string(line));
+        }
+    }
+    input.close();
+
+    int rank{};
+    for (const auto& h : hands)
+    {
+        answer += ++rank * h.bet();
+    }
+
+    std::cout << answer << std::endl;
+    return 0;
+}