protected override long?SolvePart2Impl(string input)
{
var originalInstructions = BootCodeProgram.Parse(input).GetInstructions();
for (var instructionIndex = 0; instructionIndex < originalInstructions.Count; instructionIndex++)
{
var instruction = originalInstructions[instructionIndex];
if (instruction.Operation is "jmp" or "nop")
{
var instructions = originalInstructions.ToArray();
var newOp = instruction.Operation == "jmp" ? "nop" : "jmp";
instructions[instructionIndex] = new Instruction(newOp, instruction.Argument);
try
{
var bootCodeProgram = new BootCodeProgram(instructions);
var result = bootCodeProgram.Evaluate();
Console.WriteLine($"Changed {instruction.Operation} to {newOp} at line {instructionIndex + 1} and got successful result of {result}");
return(result);
}
catch (InvalidOperationException e) when(e.Message == "Infinite loop detected")
{
// Intentionally blank, try the next instruction
}
}
}
throw new InvalidOperationException("Failed to solve Day 8 Part 2");
}
protected override long?SolvePart1Impl(string input)
{
var bootCodeProgram = BootCodeProgram.Parse(input);
try
{
bootCodeProgram.Evaluate();
}
catch (InvalidOperationException e) when(e.Message == "Infinite loop detected")
{
return(bootCodeProgram.Accumulator);
}
throw new InvalidOperationException("Expected Day 8 Part 1's puzzle input to produce an Infinite loop error, but got none.");
}
