public static BootCodeInstruction ParseBootCodeInstruction(string instructionLine)
{
var match = Regex.Match(instructionLine, @"^(\w+) ((\+|-)\d+)$");
if (!match.Success)
{
throw new Exception($"Unrecognized instruction line: {instructionLine}");
}
var instruction = match.Groups[1].Value.Trim();
var value = int.Parse(match.Groups[2].Value.Trim());
var result = new BootCodeInstruction(instruction, value);
return(result);
}
public static IList <BootCode> GetPossiblyFixedBootCodes(BootCode bootCode)
{
var result = new List <BootCode>();
for (int i = 0; i < bootCode.Instructions.Count; i++)
{
var currentInstruction = bootCode.Instructions[i];
if ("jmp".Equals(currentInstruction.Instruction) ||
"nop".Equals(currentInstruction.Instruction))
{
var instructionsCopy = bootCode.Instructions.ToList();
var newInstruction = "jmp".Equals(currentInstruction.Instruction) ? "nop" : "jmp";
instructionsCopy[i] = new BootCodeInstruction(newInstruction, currentInstruction.Value);
var newBootCode = new BootCode(instructionsCopy);
result.Add(newBootCode);
}
}
return(result);
}