public async Task <(bool IsSuccess, double?CrossingTime, string ErrorMessage)> CrossBridgeAsync(Models.Hiker hiker, Models.Bridge bridge)
{
try
{
var timeToCross = await Task.Run(() => bridge.Span / hiker.CrossingSpeed);
return(true, timeToCross, null);
}
catch (Exception ex)
{
logger?.LogError(ex.ToString());
return(false, null, ex.Message);
}
}
/// <summary>
///
/// </summary>
/// <param name="hikers"></param>
/// <param name="bridge"></param>
/// <returns></returns>
public async Task <(bool IsSuccess, double?CrossingTime, SortedList <double, Models.Hiker> SortedHikers, string ErrorMessage)> CrossBridgeAsync(SortedList <double, Models.Hiker> hikers, Models.Bridge bridge)
{
try
{
if (hikers == null)
{
hikers = new SortedList <double, Models.Hiker>();
}
foreach (var hiker in bridge.Hikers)
{
hikers.Add(hiker.CrossingSpeed, hiker);
}
if (!hikers.Any()) // no hikers at this bridge - nobody needs to cross; return zero minutes
{
return(true, 0, hikers, null);
}
else if (hikers.Count <= 2) // only one hiker at this bridge - return this hiker's crossing time
// only two hiker at this bridge - return the slower hiker's crossing time
{
var oneOrTwoeHikerResult = await hikerProvider.CrossBridgeAsync(hikers.First().Value, bridge);
return(true, oneOrTwoeHikerResult.CrossingTime, hikers, null);
}
else
{
var fastestHiker = hikers.Last().Value;
int numberOfReturnTrips = hikers.Count - 2;
var taskResult = await hikerProvider.CrossBridgeAsync(fastestHiker, bridge);
var fastestHikerCrossTime = (taskResult.IsSuccess) ? taskResult.CrossingTime.Value : 0;
double crossingTime = fastestHikerCrossTime * numberOfReturnTrips;
for (int i = 0; i <= hikers.Count - 2; i++)
{
taskResult = await hikerProvider.CrossBridgeAsync(hikers[hikers.Keys[i]], bridge);
crossingTime = (taskResult.IsSuccess) ? crossingTime + taskResult.CrossingTime.Value : crossingTime;
}
return(true, crossingTime, hikers, null);
}
}
catch (Exception ex)
{
logger?.LogError(ex.ToString());
return(false, null, null, ex.Message);
}
}
