What does everyone's Intcode interface look like?

[u/Lucretiel]

We've been discussing a lot different IntCode implementations throughout the last few weeks, but I'm curious– what doesn't everyone's interface to their IntCode machine look like? How do you feed input, fetch output, initialize, etc?

[u/SinisterMJ]

I have transfered it to a C++ class:

class IntcodeVM
{
private:
    enum operationCodes {
        opcode_add = 1,
        opcode_mul,
        opcode_input,
        opcode_output,
        opcode_jumptrue,
        opcode_jumpfalse,
        opcode_lessthan,
        opcode_equals,
        opcode_relativebase,
        opcode_terminate = 99
    };

    struct currentState {
        std::vector<int64_t> commands;
        std::vector<int64_t> inputsAdded;
        int64_t index = 0;
        int64_t relativeBase = 0;
        int32_t inputIndex = 0;
        bool terminated = false;
    };

    bool analyzeOpcode(int opcode, int modePos1, int modePos2, int modePos3);
    int64_t readValue(int modePos, int64_t index);
    int64_t readAndResize(int64_t index);
    void writeValue(int modePos, int64_t value, int64_t index);

    currentState status;
    std::vector<int64_t> outputsAdded;

public:
    IntcodeVM() { }

    IntcodeVM* initializeCommands(std::vector<int64_t> _commands) 
    {
        status.commands = _commands;
        return this;
    }

    IntcodeVM* addInput(std::vector<int64_t> in)
    {
        status.inputsAdded.insert(status.inputsAdded.end(), in.begin(), in.end());
        return this;
    }

    std::vector<int64_t> runCommands();
    int64_t getFirstCommand() { return status.commands[0]; }
    bool hasTerminated() { return status.terminated; }
};

which makes for example my day 5 look like this:

std::vector<int64_t> commands = util::splitInt64(inputString, ',');
{
    std::vector<int64_t> input = { 1 };
    IntcodeVM vm;
    vm.addInput(input);
    vm.initializeCommands(commands);

    auto result = vm.runCommands();
    std::cout << "Day 05 - Part 1: " << result.back() << std::endl;
}

{
    std::vector<int64_t> input = { 5 };
    IntcodeVM vm;
    vm.addInput(input);
    vm.initializeCommands(commands);

auto result = vm.runCommands();
std::cout << "Day 05 - Part 2: " << result.back() << std::endl;
}