Added older advents

advent_of_code_2018/day9/main1.cc

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+#include <iomanip>
+#include <iostream>
+#include <string>
+#include <vector>
+
+using namespace std;
+
+/* Slow-as-fuck solution:
+
+    $ time ./a.out < input.in
+    Num players: 468
+    Last marble: 7184300
+    Best player had a score of 3156297594
+    ./a.out < input.in  5143.54s user 1.02s system 99% cpu 1:25:53.91 total
+
+*/
+
+struct Game
+{
+    size_t num_players;
+    size_t last_marble;
+};
+
+istream &operator>>(istream &in, Game &game)
+{
+    cin >> game.num_players;
+    cin.ignore(31); // ignore ' players; last marble is worth '.
+    cin >> game.last_marble;
+    cin.ignore(8); // ignore '  points\n'
+
+    return in;
+}
+
+size_t index(size_t main, size_t size)
+{
+    main += 2;
+    main = main % size;
+    return main;
+}
+
+void print_gamestate(size_t round, vector<size_t> const &game, size_t main)
+{
+    cout << setw(7) << ("["s + to_string(round) + "]: "s);
+    for (size_t idx = 0; idx != game.size(); ++idx)
+    {
+        if (idx == main)
+            cout << setw(5) << ("("s + to_string(game[idx]) + ")"s);
+        else
+            cout << setw(5) << game[idx];
+    }
+    cout << "\n";
+}
+
+size_t insert_marble(vector<size_t> *game, size_t main, size_t marble)
+{
+    size_t before = (main + 2) % game->size();
+
+    if (before == 0)
+    {
+        game->push_back(marble);
+        return game->size() - 1;
+    }
+
+    game->insert(game->begin() + before, marble);
+    return before;
+}
+
+size_t bonus_marble(size_t main, size_t size)
+{
+    if (main < 7)
+        return size - (7 - main);
+    
+    return main - 7;
+}
+
+int main()
+{
+    Game game;
+    cin >> game;
+
+    cout << "Num players: " << game.num_players << "\n";
+    cout << "Last marble: " << game.last_marble << "\n";
+
+    size_t main_marble = 0;
+    
+    vector<size_t> players;
+    players.resize(game.num_players, 0);
+
+    vector<size_t> marbles { 0 };
+    // print_gamestate(0, marbles, main_marble);
+
+    for (size_t idx = 1; idx != game.last_marble + 1; ++idx)
+    {
+        cout << "Progress: " << idx / static_cast<float>(game.last_marble) * 100 << "\r";
+
+        if (idx % 23 == 0) //special case
+        {
+            size_t player = (idx - 1) % game.num_players;
+            players[player] += idx;
+
+            main_marble = bonus_marble(main_marble, marbles.size());
+            players[player] += marbles[main_marble];
+            marbles.erase(marbles.begin() + main_marble);
+        }
+        else
+        {
+            main_marble = insert_marble(&marbles, main_marble, idx);
+        }
+        // print_gamestate(idx, marbles, main_marble);
+    }
+
+    size_t best_player = 0;
+    for (size_t idx = 1; idx < players.size(); ++idx)
+    {
+        if (players[best_player] < players[idx])
+            best_player = idx;
+    }
+
+    cout << "Best player had a score of " << players[best_player] << "\n";
+}