public List <ArithmeticTask> RandomTasks(ArithmeticTaskRequest request, int count)
{
List <ArithmeticTask> item = tasks.FilterByRequest(request).Shuffle().Take(count)
.ToList();
return(item);
}
public static IEnumerable <ArithmeticTask> FilterByRequest(this IEnumerable <ArithmeticTask> tasks,
ArithmeticTaskRequest request)
{
tasks = tasks.Where(x =>
{
bool match = true;
if (!request.AllowTimes1)
{
match = match && x.A != 1;
}
if (!request.AllowTimes0)
{
match = match && x.A != 0;
}
match = match && request.Tables.Contains(x.B);
return(match);
});
return(tasks);
}
public ArithmeticTask RandomTask(ArithmeticTaskRequest request)
{
ArithmeticTask item = tasks.FilterByRequest(request).ToList().RandomItem();
return(item);
}
public List <ArithmeticTask> AllForTable(ArithmeticTaskRequest request)
{
return(tasks.FilterByRequest(request).ToList());
}