/*
* departure location: 43-237 or 251-961
* departure station: 27-579 or 586-953
* departure platform: 31-587 or 608-967
* departure track: 26-773 or 784-973
* departure date: 41-532 or 552-956
* departure time: 33-322 or 333-972
* arrival location: 30-165 or 178-965
* arrival station: 31-565 or 571-968
* arrival platform: 36-453 or 473-963
* arrival track: 35-912 or 924-951
* class: 39-376 or 396-968
* duration: 31-686 or 697-974
* price: 28-78 or 96-971
* route: 32-929 or 943-955
* row: 40-885 or 896-968
* seat: 26-744 or 765-967
* train: 46-721 or 741-969
* type: 30-626 or 641-965
* wagon: 48-488 or 513-971
* zone: 34-354 or 361-973
*
* your ticket:
* 151,71,67,113,127,163,131,59,137,103,73,139,107,101,97,149,157,53,109,61
*
* nearby tickets:
* 680,418,202,55,792,800,896,801,312,252,721,702,24,112,608,837,98,222,797,364
*/
internal static TicketInformation Parse(string filename)
{
var lines = File.ReadAllLines(filename);
int inputMode = 0;
var result = new TicketInformation();
for (int lineIndex = 0; lineIndex < lines.Length; lineIndex++)
{
var line = lines[lineIndex];
if (line == string.Empty)
{
inputMode++;
continue;
}
if (line == "your ticket:" || line == "nearby tickets:")
{
continue;
}
switch (inputMode)
{
case 0:
{
var parts = line.Split(": ");
var ranges = parts[1].Split(" or ");
var rangeA = ranges[0].Split("-").Select(n => int.Parse(n)).ToArray();
var rangeB = ranges[1].Split("-").Select(n => int.Parse(n)).ToArray();
result.Details.Add(parts[0], new TicketRange[]
{
new TicketRange(rangeA[0], rangeA[1]),
new TicketRange(rangeB[0], rangeB[1])
});
}
break;
case 1:
{
var numbers = line.Split(',');
result.MyTicket = numbers.Select(n => int.Parse(n)).ToArray();
}
break;
case 2:
{
var numbers = line.Split(',');
result.NearbyTickets.Add(numbers.Select(n => int.Parse(n)).ToArray());
}
break;
}
}
return(result);
}
public static string Run(TicketInformation ticketInformation)
{
var invalidNumbers = new List <int>();
var validTickets = new List <int[]>();
var suspectedKeys = new Dictionary <int, List <string> >();
for (int n = 0; n < ticketInformation.MyTicket.Length; n++)
{
suspectedKeys.Add(n, ticketInformation.Details.Keys.ToList());
}
foreach (var nearbyTicket in ticketInformation.NearbyTickets)
{
bool validTicket = true;
for (var index = 0; index < nearbyTicket.Length; index++)
{
var value = nearbyTicket[index];
bool validForAtleastOneField = false;
foreach (var detail in ticketInformation.Details)
{
var ranges = detail.Value;
if ((ranges[0].From <= value && ranges[0].To >= value) ||
(ranges[1].From <= value && ranges[1].To >= value))
{
validForAtleastOneField = true;
}
}
if (!validForAtleastOneField)
{
invalidNumbers.Add(value);
validTicket = false;
}
}
if (validTicket)
{
validTickets.Add(nearbyTicket);
}
}
foreach (var ticket in validTickets)
{
for (int index = 0; index < ticket.Length; index++)
{
var value = ticket[index];
foreach (var detail in ticketInformation.Details)
{
var ranges = detail.Value;
var notInRange = (ranges[0].From > value || ranges[0].To < value) &&
(ranges[1].From > value || ranges[1].To < value);
if (notInRange && suspectedKeys[index].Contains(detail.Key))
{
suspectedKeys[index].Remove(detail.Key);
}
}
}
}
var listOfKeys = new HashSet <string>(ticketInformation.Details.Keys);
while (listOfKeys.Count > 0)
{
var lonelyKey = suspectedKeys.Where(k => k.Value.Count == 1 && listOfKeys.Contains(k.Value[0])).First().Value.Single();
foreach (var keyValuePair in suspectedKeys)
{
if (keyValuePair.Value.Count > 1 && keyValuePair.Value.Contains(lonelyKey))
{
suspectedKeys[keyValuePair.Key].Remove(lonelyKey);
}
}
listOfKeys.Remove(lonelyKey);
}
// Unnecessary rewrite to "detail => value" form, but I wanted it in that form as a design choice.
var detailInformation = new Dictionary <string, int>();
foreach (var suspectedKey in suspectedKeys)
{
detailInformation.Add(suspectedKey.Value[0], suspectedKey.Key);
}
long total = 1;
foreach (var detail in detailInformation.Where(k => k.Key.StartsWith("departure")))
{
total *= ticketInformation.MyTicket[detail.Value];
}
return(total.ToString());
}
