/// <summary>
/// 寻找解，找不到时返回"answer not found\r\n"
/// <para>每个解占一行</para>
/// </summary>
/// <param name="equation">要找的方程</param>
/// <returns></returns>
public async Task <string> get_results(BaseEquation equation)
{
string ret = "answer not found\r\n";
LinkedList <SubEquation> sorted_equation_list = new LinkedList <SubEquation>();
List <SubEquation> calculated_equation_list = new List <SubEquation>();
SubEquation root = new SubEquation(equation);
sorted_equation_list = sorted_insert(sorted_equation_list, calculated_equation_list, root);
SubEquation first_ans = null;
bool already_first = false;
while (true)
{
if (sorted_equation_list.Count == 0)
{
break;
}
ConsoleMazeMain.BaseEquationEventArgs ee = new ConsoleMazeMain.BaseEquationEventArgs();
ee.be = sorted_equation_list.First.Value;
callback(this, ee);
bool bk = false;
await Task.Run(() =>
{
if (sorted_equation_list.First.Value.ans_found)
{
if (ret == "answer not found\r\n")
{
first_ans = sorted_equation_list.First.Value;
ret = "";
}
ret += sorted_equation_list.First.Value.equation_console + "\r\n";
bk = true;
return;
}
LinkedListNode <SubEquation> now = sorted_equation_list.First;
sorted_equation_list.RemoveFirst();
List <char> ava_l = now.Value.available_letters_from_last(1);
List <int> ava_n = now.Value.available_nums();
for (int i = 0; i < ava_n.Count; i++)
{
if (ava_n[i] == 0)
{
int first_l = now.Value.get_first_in_each_line().IndexOf(ava_l[0]);
if (first_l != -1 && now.Value.spilt_string_without_operator[first_l].Length > 1)
{
continue;
}
}
string new_eva = now.Value.replace(ava_l[0], ava_n[i]);
SubEquation new_eq = new SubEquation(new_eva);
if (new_eq.ans_found)
{
if (ret == "answer not found\r\n")
{
first_ans = new_eq;
ret = "";
}
ret += new_eq.equation_console + "\r\n";
continue;
}
sorted_equation_list = sorted_insert(sorted_equation_list, calculated_equation_list, new_eq);
}
});
if (first_ans != null && !already_first)
{
ConsoleMazeMain.BaseEquationEventArgs ee2 = new ConsoleMazeMain.BaseEquationEventArgs();
ee2.be = first_ans;
ee2.is_ans = true;
callback(this, ee2);
already_first = true;
}
if (bk)
{
break;
}
}
return(ret);
}
private static LinkedList <SubEquation> sorted_insert(LinkedList <SubEquation> list, List <SubEquation> calculated, SubEquation to_insert)
{
if (to_insert.node_point.compare_to(0) < 0)
{
return(list);
}
if (list.Count == 0)
{
list.AddFirst(to_insert);
calculated.Add(to_insert);
}
else
{
for (int i = 0; i < calculated.Count; i++)
{
if (to_insert.same_as(calculated[i]))
{
return(list);
}
}
LinkedListNode <SubEquation> now = list.First;
bool inserted = false;
for (int i = 0; i < list.Count; i++)
{
if (to_insert.node_point.compare_to(now.Value.node_point) < 0)
{
list.AddBefore(now, to_insert);
calculated.Add(to_insert);
inserted = true;
break;
}
now = now.Next;
}
if (!inserted)
{
list.AddLast(to_insert);
calculated.Add(to_insert);
}
}
return(list);
}