#include <fstream>
#include <iostream>
#include <string>
#include <vector>
#include <unordered_set>
#include <algorithm>
#include <optional>

using namespace std;
unordered_set<short> visited_by_original;
unordered_set<short> visited;
vector<pair<char, short>> program;

optional<int> run(int pc = 0, int acc = 0, bool original = true) {
    int part_2_solution;
    while (original && !visited_by_original.count(pc) || !visited.count(pc)) {
        if (original) visited_by_original.insert(pc);
        visited.insert(pc);
        if (pc >= program.size())
            return acc;
        auto instruction = program[pc];
        if (instruction.first == 'a') acc += instruction.second;
        else if (original) {
            auto changed_result = run(pc + (instruction.first == 'j' ? 1 : instruction.second), acc, false);
            if (changed_result.has_value())
                part_2_solution = changed_result.value();
        }
        pc += instruction.first == 'j' ? instruction.second : 1;
    }
    if (original)
        cout << "part 1: " << acc << endl << "part 2: " << part_2_solution << endl;
    return {};
}

int main() {
    auto split = [](string in, string delim) {
        vector<string> result;
        while (true) {
            auto pos = in.find(delim);
            result.push_back(in.substr(0, pos));
            in = in.substr(pos == string::npos ? in.length() : pos + delim.length());
            if (!in.length()) return result;
        }
    };

    for (auto& line : split(string(istreambuf_iterator<char>(ifstream("input-8.txt").rdbuf()), istreambuf_iterator<char>()), "\n"))
        if(line.length())
            program.push_back(make_pair(line[0], stoi(line.substr(4))));

    run();
    system("pause");
    return 0;
}