public Task(long id, string n, Campus c, List <TaskDict> dic, Task prev)
: this(id, n, c, dic, prev != null ? prev.Id : -1)
{
}
public Task(long id, string n, Campus c, List <TaskDict> dic, Task prev)
: this(id, n, c, dic, prev != null ? prev.Id : -1)
{
}