Lists - 1.1(2 sem)

Program Lab_1_1;

{$APPTYPE CONSOLE}

Uses
    SysUtils,
    Math,
    Windows;

Type
    TPElement = ^TElement;
    TElement = Record
      Coefficient: Integer;
      Degree: Integer;
      Next: TPElement;
    End;

Function Meaning(P: TPElement; X: Integer): Integer; //вычисляет значение, подставляю х
Var
    Sum: Integer;
Begin
    Sum := 0;

    While P <> Nil Do
    Begin
      Sum := Sum + P^.Coefficient * Round(Power(X, P^.Degree));
      P := P^.Next;
    End;

    Meaning := Sum;
End;

Function Equality(P, Q: TPElement): Boolean; //провряет равенство многочленов
Var
    IsEqual: Boolean;
Begin
    IsEqual := True;

    While (P <> Nil) And (Q <> Nil) And IsEqual Do
    Begin
        If (P = Nil) And (Q = Nil) Then
          IsEqual := False
        Else
        Begin
            If (P^.Degree <> Q^.Degree) Or (P^.Coefficient <> Q^.Coefficient) Then
              IsEqual := False;
            P := P^.Next;
            Q := Q^.Next;
        End;
    End;

    Equality := IsEqual;
End;

Procedure Add(Var R: TPElement; P, Q: TPElement); // создание 3 многочлена из двух
Var
  X, Y: TPElement;
Begin
    New(X);
    New(Y);
    R := X;

    While (P <> Nil) And (Q <> Nil) Do
    Begin
        If P^.Degree > Q^.Degree Then
        Begin
            X^.Degree := P^.Degree;
            X^.Coefficient := P^.Coefficient;
            P := P^.Next;
        End
        Else
        If P^.Degree < Q^.Degree Then
        Begin
            X^.Degree := Q^.Degree;
            X^.Coefficient := Q^.Coefficient;
            Q := Q^.Next;
        End
        Else
        Begin
            X^.Degree := P^.Degree;
            X^.Coefficient := P^.Coefficient + Q^.Coefficient;
            P := P^.Next;
            Q := Q^.Next;
        End;

        Y := X;
        New(X);
        Y^.Next := X;
    End;

    Y^.Next := Nil;
End;

Function InputList(Degree: Integer): TPElement; //ввод
Var
    Element, X, Y: TPElement;
    I, Coefficient: Integer;
Begin
    New(X);
    New(Y);
    Element := X;

    For I := Degree Downto 0 Do
    Begin
        If I <> 0 Then
        Begin
            Write('X^', I, ' * ');
            Read(Coefficient);
            Write(' + ');
        End
        Else
        Begin
            Readln(Coefficient);
        End;

        If Coefficient <> 0 Then
        Begin
            X^.Coefficient := Coefficient;
            X^.Degree := I;
            Y := X;
            New(X);
            Y^.Next := X;
        End;
    End;

    Y^.Next := Nil;
    InputList := Element;
End;

Procedure OutputList(List: TPElement); // вывод
Var
    IsFirstElement: Boolean;
Begin
    IsFirstElement := True;

    While List <> Nil Do
    Begin
        If Not IsFirstElement Then
            Write(' + ');
        IsFirstElement := False;
        If List^.Degree <> 0 Then
            Write(List^.Coefficient, 'X^', List^.Degree)
        Else
            Write(List^.Coefficient);
        List := List^.Next;
    End;

    Writeln;
End;

//Main
Var
  P, Q, R: TPElement;
  Degree, X: Integer;
Begin
    //Ввод
    Write('Введите степень многочлена P(X): ');
    Readln(Degree);
    Writeln('Введите коэффициенты: ');
    P := InputList(Degree);
    Write('Введите степень многочлена Q(X): ');
    Readln(Degree);
    Writeln('Введите коэффициенты: ');
    Q := InputList(Degree);
    Write('Многочлен P(X): ');
    OutputList(P);
    Write('Многочлен Q(X): ');
    OutputList(Q);
    Add(R, P, Q);
    Write('Многочлен R(X) = P(X) + Q(X): ');
    OutputList(R);
    Write('Введите значение X: ');
    Readln(X);
    //Вычисление
    Writeln('Q(X) = ', Meaning(Q, X));
    Writeln('P(X) = ', Meaning(P, X));
    Writeln('R(X) = ', Meaning(R, X));
    Write('Равны ли Q(X) и P(X)? Ответ: ');
    If Equality(P, Q) Then
        Write('Равны')
    Else
        Write('Неравны');

    Readln;
End.