Day19.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Drawing;
using System.Text.RegularExpressions;
using System.Diagnostics;
using System.Runtime.Serialization;

namespace AdventOfCode2018
{
    /*
10 -> bani
1 -> muli
2 -> bori
8 -> borr
4 -> addi
14 -> seii
0 -> banr
13 -> mulr
11 -> addr
3 -> setr
9 -> eqri
7 -> gtir
15 -> gtrr
12 -> eqir
6 -> gtri
5 -> eqrr     
     */

    class Day19 : Day
    {
        public override bool Test()
        {
            return Utils.Test(Part1, testInput, "6");
        }

        int r0 = 0;

        public override string Part1(string input, dynamic options)
        {
            var ipr = int.Parse(input.Substring(4,1));
            var program = RegexDeserializable.Deserialize<Statement>(input.Substring(7)).ToArray();

            var opcodes = AllOps.ToDictionary(o => o.name);
            opcodes["seti"] = opcodes["seii"];

            var registers = new[] { r0, 0, 0, 0, 0, 0 };
            var ip = 0;

            while (ip >= 0 && ip < program.Length)
            {

                var statement = program[ip];
                var op = opcodes[statement.opcode];

                if (ip > 13)
                    Console.WriteLine(ip.ToString("00") + " - " + string.Join(", ", registers.Select(r => r.ToString("0000"))) + " " + statement.opcode + " " + statement.p0 + " " + statement.p1 + " " + statement.p2);

                registers[ipr] = ip;
                op.Apply(statement.p0, statement.p1, statement.p2, registers);
                ip = registers[ipr];
                ip++;

            }

            return registers[0].ToString();

        }

        public override string Part2(string input, dynamic options)
        {
            /*r0 = 1;
            return Part1(Input, options);*/

            var ret = 0;
            for (int i = 1; i <= 10551376; i++)
            {
                if (10551376 % i == 0)
                {
                    ret += i;
                }
            }

            return ret.ToString();
        }

        List<Dictionary<int, Op>> allsolutions = new List<Dictionary<int, Op>>();

        private void findMatches(Dictionary<int, Op> opcodes, Dictionary<int, IEnumerable<Op>> data)
        {
            var allunused = data.Where(d => !opcodes.ContainsKey(d.Key)).Select(d => new { opcode = d.Key, possibleOps = d.Value.Where(o => !opcodes.ContainsValue(o)) }).OrderBy(d => d.possibleOps.Count());

            var unused = allunused.FirstOrDefault();

            if (unused != null)
            {
                foreach (var possibleOp in unused.possibleOps)
                {
                    opcodes[unused.opcode] = possibleOp;
                    findMatches(opcodes, data);
                }

                opcodes.Remove(unused.opcode);

            }
            else
            {
                var copy = new Dictionary<int, Op>(opcodes);

                /*if (!allsolutions.Any(s => s.OrderBy(k => k.Key).SequenceEqual(copy.OrderBy(k => k.Key))))
                {
                    allsolutions.Add(copy);
                    foreach (var kv in copy)
                    {
                        Console.Write(kv.Key + ":" + kv.Value.name + " ");
                    }
                    Console.WriteLine();
                }*/

                throw new CompleteException();
            }

        }

        private Op[] AllOps = new Op[]
        {
            new Op("banr", (a,b) => a&b),
            new Op("muli", (a,b) => a*b),
            new Op("bori", (a,b) => a|b),
            new Op("setr", (a,b) => a),
            new Op("addi", (a,b) => a+b),
            new Op("eqrr", (a,b) => a == b ? 1 : 0),
            new Op("gtri", (a,b) => a > b ? 1 : 0),
            new Op("gtir", (a,b) => a > b ? 1 : 0),
            new Op("borr", (a,b) => a|b),
            new Op("eqri", (a,b) => a == b ? 1 : 0),
            new Op("bani", (a,b) => a&b),
            new Op("addr", (a,b) => a+b),
            new Op("eqir", (a,b) => a == b ? 1 : 0),
            new Op("mulr", (a,b) => a*b),
            new Op("seii", (a,b) => a),
            new Op("gtrr", (a,b) => a > b ? 1 : 0),
        };

        [RegexDeserializable(@"^(?<opcode>\w+) (?<p0>\d+) (?<p1>\d+) (?<p2>\d+)")]
        public class Statement
        {
            public string opcode;
            public int p0;
            public int p1;
            public int p2;
        }

        public class Op
        {
            private Func<int, int, int> fn;
            private bool r1;
            private bool r2;
            public string name;

            public Op(string name, Func<int, int, int> fn)
            {
                this.name = name;
                this.fn = fn;
                r1 = name[2] != 'i';
                r2 = name[3] != 'i';
            }

            public void Apply(int a1, int a2, int a3, int[] registers)
            {
                a1 = r1 ? registers[a1] : a1;
                a2 = r2 ? registers[a2] : a2;
                registers[a3] = fn(a1, a2);
            }
        }


        private string testInput =
@"#ip 0
seti 5 0 1
seti 6 0 2
addi 0 1 0
addr 1 2 3
setr 1 0 0
seti 8 0 4
seti 9 0 5";

        [Serializable]
        private class CompleteException : Exception
        {
            public CompleteException()
            {
            }

            public CompleteException(string message) : base(message)
            {
            }

            public CompleteException(string message, Exception innerException) : base(message, innerException)
            {
            }

            protected CompleteException(SerializationInfo info, StreamingContext context) : base(info, context)
            {
            }
        }
    }

}

/*

03 - 0000, 0001, 0976, 0000, 0002, 0004 mulr 1 5 3 # mult r5 * r1 === 1, so move 5 to 3
04 - 0000, 0001, 0976, 0004, 0003, 0004 eqrr 3 2 3 # set 3 to zero iff eq r2
05 - 0000, 0001, 0976, 0000, 0004, 0004 addr 3 4 4 # add r3 to the ip, will jump to 7 when r3 is r2
06 - 0000, 0001, 0976, 0000, 0005, 0004 addi 4 1 4 # add 1 to r4, jump to 8
(07 addr 1 0 0)
08 - 0000, 0001, 0976, 0000, 0007, 0004 addi 5 1 5 # add 1 to r5
09 - 0000, 0001, 0976, 0000, 0008, 0005 gtrr 5 2 3 # if r5 > r2 then r3 = 1
10 - 0000, 0001, 0976, 0000, 0009, 0005 addr 4 3 4 # add r3 to ip - so jump to 12 iff r5 > r2
11 - 0000, 0001, 0976, 0000, 0010, 0005 seti 2 2 4 # set ip to 2
03 - 0000, 0001, 0976, 0000, 0002, 0005 mulr 1 5 3
04 - 0000, 0001, 0976, 0005, 0003, 0005 eqrr 3 2 3
05 - 0000, 0001, 0976, 0000, 0004, 0005 addr 3 4 4
06 - 0000, 0001, 0976, 0000, 0005, 0005 addi 4 1 4
08 - 0000, 0001, 0976, 0000, 0007, 0005 addi 5 1 5
09 - 0000, 0001, 0976, 0000, 0008, 0006 gtrr 5 2 3
10 - 0000, 0001, 0976, 0000, 0009, 0006 addr 4 3 4
11 - 0000, 0001, 0976, 0000, 0010, 0006 seti 2 2 4
03 - 0000, 0001, 0976, 0000, 0002, 0006 mulr 1 5 3
04 - 0000, 0001, 0976, 0006, 0003, 0006 eqrr 3 2 3
05 - 0000, 0001, 0976, 0000, 0004, 0006 addr 3 4 4
06 - 0000, 0001, 0976, 0000, 0005, 0006 addi 4 1 4
08 - 0000, 0001, 0976, 0000, 0007, 0006 addi 5 1 5
09 - 0000, 0001, 0976, 0000, 0008, 0007 gtrr 5 2 3
10 - 0000, 0001, 0976, 0000, 0009, 0007 addr 4 3 4
11 - 0000, 0001, 0976, 0000, 0010, 0007 seti 2 2 4


    */