/// <summary>
/// Writes an output structure to a file
/// </summary>
/// <param name="output">The structure to write</param>
/// <param name="outputFileName">The file to write to</param>
private static void WriteOutput(OutputStructure output, string outputFileName)
{
//for example
using (var outfile = File.CreateText(outputFileName))
{
if (output == null)
{
return;
}
outfile.WriteLine(output.CacheServerDescriptions.Length);
foreach (var o in output.CacheServerDescriptions)
{
outfile.Write($"{o.Id} ");
foreach (var v in o.VideoIds)
{
outfile.Write($"{v} ");
}
outfile.WriteLine();
}
}
}
public static int Score(InputStructure input, OutputStructure output)
{
var cacheServers = output.CacheServerDescriptions
.ToDictionary(
x => x.Id,
x => x.VideoIds.ToArray());
long sumSaved = 0;
long sumRequests = 0;
input.Descriptions
.AsParallel()
.ForAll(req =>
{
var Rv = req.VideoId;
var Re = req.EndpointId;
var L = input.Endpoints[Re];
var Ld = input.Endpoints[Re].Latency;
var fastestCacheServer = L.Connections
.Select(x => new { Latency = x.Latency, Cache = cacheServers[x.Id] })
.Where(x => x.Cache.Contains(Rv))
.OrderBy(x => x.Latency)
.FirstOrDefault();
var cacheServerLatency = fastestCacheServer?.Latency ?? int.MaxValue;
var Lmin = Math.Min(cacheServerLatency, Ld);
var saved = Ld - Lmin;
var savedMicro = saved;
Interlocked.Add(ref sumSaved, savedMicro * req.NumRequests);
Interlocked.Add(ref sumRequests, req.NumRequests);
});
return((int)((sumSaved * 1000) / sumRequests));
}