day20a.cpp

#include "utils.hpp"

int main(int argc, char *argv[])
{
    auto input = read_input("day20_input");
    std::vector<std::pair<int, int>> initial_values{};
    std::vector<std::pair<int, int>> current_values{};

    int position = 0;
    for (auto &&x : input)
    {
        initial_values.push_back(std::make_pair(std::stoi(x), position));
        position++;
    }
    current_values = initial_values;

    for (auto &&x : initial_values)
    {
        auto it = std::find(current_values.begin(), current_values.end(), x);
        if (it != current_values.end())
        {
            auto index = std::distance(current_values.begin(), it);
            auto new_index = (index + it->first);
            new_index = ((new_index % ((long)current_values.size()-1)) + ((long)current_values.size()-1)) % ((long)current_values.size()-1);
            if (new_index == 0)
            {
                new_index = (long)current_values.size() - 1;
            }
            current_values.erase(it);
            auto new_it = current_values.begin() + new_index;
            current_values.insert(new_it, x);
        }
    }
    auto it = std::find(current_values.begin(), current_values.end(), std::make_pair(0,4333));
    auto index = std::distance(current_values.begin(), it);
    int val_thing = ((int)index + 1000) % current_values.size();
    int val_thing_2 = ((int)index + 2000) % current_values.size();
    int val_thing_3 = ((int)index + 3000) % current_values.size();
    std::cout << current_values[val_thing].first << "\n";
    std::cout << current_values[val_thing_2].first << "\n";
    std::cout << current_values[val_thing_3].first << "\n";
    std::cout << current_values[val_thing].first + current_values[val_thing_2].first + current_values[val_thing_3].first << "\n";
}