On the way to Jupiter, you're pulled over by the Space Police.

"Attention, unmarked spacecraft! You are in violation of Space Law! All spacecraft must have a clearly visible registration identifier! You have 24 hours to comply or be sent to Space Jail!"

Read the full puzzle.

using System;
using System.Collections.Generic;
using System.Linq;

namespace AdventOfCode.Y2019.Day11;

[ProblemName("Space Police")]
class Solution : Solver {

    public object PartOne(string input) => Run(input, 0).Count;

    public object PartTwo(string input) {
        var dict = Run(input, 1);
        var irowMin = dict.Keys.Select(pos => pos.irow).Min();
        var icolMin = dict.Keys.Select(pos => pos.icol).Min();
        var irowMax = dict.Keys.Select(pos => pos.irow).Max();
        var icolMax = dict.Keys.Select(pos => pos.icol).Max();
        var crow = irowMax - irowMin + 1;
        var ccol = icolMax - icolMin + 1;
        var st = "";
        for (var irow = 0; irow < crow; irow++) {
            for (var icol = 0; icol < ccol; icol++) {
                st +=  " #"[dict.GetValueOrDefault((irowMin + irow, icolMin + icol), 0)];
            }
            st += "\n";
        }

        return st.Ocr();
    }

    Dictionary<(int irow, int icol), int> Run(string input, int startColor) {
        var mtx = new Dictionary<(int irow, int icol), int>();
        (int irow, int icol) pos = (0, 0);
        (int drow, int dcol) dir = (-1, 0);
        mtx[(0, 0)] = startColor;
        var icm = new IntCodeMachine(input);
        while (true) {
            var output = icm.Run(mtx.GetValueOrDefault(pos, 0));
            if (icm.Halted()) {
                return mtx;
            }
            mtx[pos] = (int)output[0];
            dir = output[1] switch {
                0 => (-dir.dcol, dir.drow),
                1 => (dir.dcol, -dir.drow),
                _ => throw new ArgumentException()
            };
            pos = (pos.irow + dir.drow, pos.icol + dir.dcol);
        }
    }

    
}

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