public static IList<int> GetInvalidNearbyTicketValuesForAllFields(TicketData ticketData)
{
var result = new List<int>();
foreach (var nearbyTicket in ticketData.NearbyTickets)
{
foreach (var value in nearbyTicket.FieldValues)
{
var isValid = GetIsValidValueForAnyField(value, ticketData.TicketFields);
if (!isValid)
{
result.Add(value);
}
}
}
return result;
}
public static TicketData ParseInputLines(IList<string> inputLines)
{
var ticketFieldInputLines = new List<string>();
var yourTicketInputLine = string.Empty;
var nearbyTicketInputLines = new List<string>();
bool isProcessingYourTicket = false;
bool isProcessingNearbyTickets = false;
foreach (var inputLine in inputLines)
{
if (string.IsNullOrWhiteSpace(inputLine))
continue;
if (isProcessingYourTicket)
{
if ("nearby tickets:".Equals(inputLine))
{
isProcessingYourTicket = false;
isProcessingNearbyTickets = true;
continue;
}
yourTicketInputLine = inputLine;
}
else if (isProcessingNearbyTickets)
{
nearbyTicketInputLines.Add(inputLine);
}
else
{
if ("your ticket:".Equals(inputLine))
{
isProcessingYourTicket = true;
continue;
}
ticketFieldInputLines.Add(inputLine);
}
}
var ticketFields = ParseTicketFieldInputLines(ticketFieldInputLines);
var yourTicket = ParseTicketInputLine(yourTicketInputLine);
var nearbyTickets = ParseTicketInputLines(nearbyTicketInputLines);
var result = new TicketData(ticketFields, yourTicket, nearbyTickets);
return result;
}
public static IList<Ticket> GetNearbyTicketsWithNoInvalidValues(TicketData ticketData)
{
var result = new List<Ticket>();
foreach (var nearbyTicket in ticketData.NearbyTickets)
{
bool isInvalidTicket = false;
foreach (var value in nearbyTicket.FieldValues)
{
var isValid = GetIsValidValueForAnyField(value, ticketData.TicketFields);
if (!isValid)
{
isInvalidTicket = true;
break;
}
}
if (!isInvalidTicket)
{
result.Add(nearbyTicket);
}
}
return result;
}
public static Dictionary<string, int> GetFieldIndexes(TicketData ticketData)
{
var result = new Dictionary<string, int>();
var validTickets = GetNearbyTicketsWithNoInvalidValues(ticketData);
var indexTicketFieldCandidates = new Dictionary<int, IList<TicketField>>();
for (int fieldIndex = 0; fieldIndex < ticketData.TicketFields.Count; fieldIndex++)
{
var possibleTicketFields = GetTicketFieldsThatWorkForIndex(
fieldIndex,
validTickets,
ticketData.TicketFields);
indexTicketFieldCandidates[fieldIndex] = possibleTicketFields;
}
while (indexTicketFieldCandidates.Count > 0)
{
var currentCandidate = indexTicketFieldCandidates
.OrderBy(kvp => kvp.Value.Count)
.First();
if (currentCandidate.Value.Count != 1)
{
throw new Exception("Non-deterministic candidate found");
}
var fieldIndex = currentCandidate.Key;
var ticketField = currentCandidate.Value[0];
result[ticketField.Name] = fieldIndex;
indexTicketFieldCandidates.Remove(fieldIndex);
foreach (var kvp in indexTicketFieldCandidates)
{
kvp.Value.Remove(ticketField);
}
foreach (var kvp in indexTicketFieldCandidates)
{
if (kvp.Value.Count == 0)
indexTicketFieldCandidates.Remove(kvp.Key);
}
}
return result;
}