Lab 6.2 (Delphi)

unit Unit1;

interface

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
    System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Vcl.Grids, Vcl.Menus;

type
    TForm1 = class(TForm)
    ButtonSolve: TButton;
        Memo1: TMemo;
        StringGridPoints: TStringGrid;
    ButtonPoints: TButton;
        EditAmount: TEdit;
        MainMenu1: TMainMenu;
        N1: TMenuItem;
        N2: TMenuItem;
        N3: TMenuItem;
        N5: TMenuItem;
        N6: TMenuItem;
        N7: TMenuItem;
        N8: TMenuItem;
        OpenDialog1: TOpenDialog;
        SaveDialog1: TSaveDialog;
        procedure ButtonSolveClick(Sender: TObject);
        procedure ButtonPointsClick(Sender: TObject);
        procedure FormCreate(Sender: TObject);
        procedure EditAmountKeyPress(Sender: TObject; var Key: Char);
        procedure EditAmountChange(Sender: TObject);
        procedure StringGridPointsKeyPress(Sender: TObject; var Key: Char);
        procedure StringGridPointsSetEditText(Sender: TObject;
          ACol, ARow: Integer; const Value: string);
        procedure N3Click(Sender: TObject);
        procedure N8Click(Sender: TObject);
        procedure N5Click(Sender: TObject);
        procedure N6Click(Sender: TObject);
        procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
        procedure N2Click(Sender: TObject);
    private
        { Private declarations }
    public
        { Public declarations }
    end;

    TPoint = record
        X, Y: Real;
    end;

    TLine = record
        K, B: Real;
    end;

var
    Form1: TForm1;
    Points: TArray<TPoint>;
    LineWithMostPoints: TLine;
    IsFileOpen: Boolean;
    Path: String;

implementation

{$R *.dfm}

function FindLineWithMostPoints(const Points: TArray<TPoint>): TLine;
var
    ResultLine: TLine;
    MaxPointsCount, PointsOnLine, I, J, P: Integer;
    K, B: Real;
begin
    ResultLine.K := 0;
    ResultLine.B := 0;
    MaxPointsCount := 0;

    for I := 0 to High(Points) do
    begin
        for J := I + 1 to High(Points) do
        begin

            PointsOnLine := 2; // Две уже минимум есть

            if (Points[J].X - Points[I].X) <> 0 then
                K := (Points[J].Y - Points[I].Y) / (Points[J].X - Points[I].X)
            Else
                Dec(PointsOnLine);

            B := Points[I].Y - K * Points[I].X;

            for P := 0 to High(Points) do
            begin
                if (P <> I) and (P <> J) and
                  (Abs(Points[P].Y - (K * Points[P].X + B)) < 0.0001) then
                    Inc(PointsOnLine);
            end;

            if PointsOnLine > MaxPointsCount then
            begin
                MaxPointsCount := PointsOnLine;
                ResultLine.K := K;
                ResultLine.B := B;
            end;
        end;
    end;

    Result := ResultLine;
end;

procedure TForm1.ButtonSolveClick(Sender: TObject);
var
    Size, I: Integer;
begin
    Size := StrToInt(EditAmount.Text);
    SetLength(Points, Size);
    for I := 0 to Size - 1 do
    Begin
        Points[I].X := StrToFloat(StringGridPoints.Cells[I + 1, 1]);
        Points[I].Y := StrToFloat(StringGridPoints.Cells[I + 1, 2]);
    End;
    LineWithMostPoints := FindLineWithMostPoints(Points);
    N6.Enabled := True;
    Memo1.Text := 'Уравнение прямой с большинством точек: y = ' +
      FloatToStr(LineWithMostPoints.K) + 'x + ' +
      FloatToStr(LineWithMostPoints.B);
end;

procedure TForm1.ButtonPointsClick(Sender: TObject);
var
    I: Integer;
begin
    StringGridPoints.Enabled := True;
    StringGridPoints.Rows[1].Clear;
    StringGridPoints.Rows[2].Clear;
    StringGridPoints.Cells[0, 1] := 'X';
    StringGridPoints.Cells[0, 2] := 'Y';

    StringGridPoints.ColCount := StrToInt(EditAmount.Text) + 1;
    For I := 1 to StringGridPoints.ColCount do
        StringGridPoints.Cells[I, 0] := IntToStr(I);

    Memo1.Clear;
    ButtonSolve.Enabled := False;
    N6.Enabled := False;
end;

procedure TForm1.EditAmountChange(Sender: TObject);
var
    Num: Integer;
    IsCorrect: Boolean;
begin
    IsCorrect := True;
    try
        Num := StrToInt(EditAmount.Text)
    Except
        IsCorrect := False;
    end;
    if IsCorrect And (Num > 1) And (Num <= 20) then
        ButtonPoints.Enabled := True
    Else
    Begin
        ButtonPoints.Enabled := False;
        IsCorrect := False;
    End;
    StringGridPoints.Enabled := False;
    ButtonSolve.Enabled := False;
    Memo1.Clear;
    N6.Enabled := False
end;

procedure TForm1.EditAmountKeyPress(Sender: TObject; var Key: Char);
begin
    If not(Key in ['0' .. '9', #13, #8]) Then
        Key := #0;
    if (ButtonPoints.Enabled = True) And (Key = #13) then
        ButtonPoints.Click
end;

procedure TForm1.FormCloseQuery(Sender: TObject; var CanClose: Boolean);
begin
    CanClose := Application.MessageBox('Вы действительно хотите выйти?',
      'Выход', MB_ICONQUESTION + MB_YESNO) = ID_YES;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
    StringGridPoints.Cells[0, 0] := '№/№';
    StringGridPoints.Cells[0, 1] := 'X';
    StringGridPoints.Cells[0, 2] := 'Y';
end;

procedure TForm1.N2Click(Sender: TObject);
const
    Info1 = 'На плоскости заданы n точек своими координатами. Найти уравнение'#13#10;
    Info2 = 'прямой, которой принадлежит наибольшее число данных точек.'#13#10;
    Info3 = '1. Минимальное количество точек - 2, максимальная - 20.'#13#10;
    Info4 = '2. Диапазон ввода координат от 0 до 99.'#13#10;
begin
    Application.MessageBox(Info1 + Info2 + Info3 + Info4, 'Справка', 0);
end;

procedure TForm1.N3Click(Sender: TObject);
begin
    Application.MessageBox('Сымоник Вадим, гр. 251004', 'О разработчике', 0)
end;

Function GetSize(var FileInput: TextFile): String;
Const
    MIN_NUM = 2;
    MAX_NUM = 20;
Var
    Size, Num: Integer;
    Str: String;
    IsCorrect: Boolean;
Begin
    Size := 0;
    Str := '';
    If Not Eof(FileInput) Then
    Begin
        IsCorrect := True;
        Try
            Read(FileInput, Size);
        Except
            MessageBox(Form1.Handle, PChar('Недопустимый размер массива!'),
              'Ошибка', MB_ICONSTOP);
            IsCorrect := False;
            Size := 0;
        End;
    End
    Else
        MessageBox(Form1.Handle, PChar('Недостаточно данных в файле!'),
          'Ошибка', MB_ICONSTOP);
    If (Size >= MIN_NUM) And (Size <= MAX_NUM) Then
        Str := IntToStr(Size)
    Else
        Application.MessageBox('Проверьте корректность данных в файле',
          'Ошибка', 0);
    GetSize := Str;
End;

Function TakeInformationIntoCell(Var FileInput: TextFile;
  Var IsCorrect: Boolean): String;
Var
    Temp: Integer;
    Str: String;
Begin
    If Not Eof(FileInput) Then
    Begin
        Try
            Read(FileInput, Temp);
            Str := IntToStr(Temp);
        Except
            MessageBox(Form1.Handle, PChar('Неверные данные!'), 'Ошибка',
              MB_ICONSTOP);
            IsCorrect := False;
        End;
        If IsCorrect And (Temp < 0) And (Temp >= 100) Then
        Begin
            IsCorrect := False;
            MessageBox(Form1.Handle,
              PChar('Недопустимый диапазон входных данных!'), 'Ошибка',
              MB_ICONSTOP);
            Str := '';
        End;
    End
    Else
    Begin
        IsCorrect := False;
        MessageBox(Form1.Handle, PChar('Недостаточно значений в файле!'),
          'Ошибка', MB_ICONSTOP);
        Str := '';
    End;
    TakeInformationIntoCell := Str;
End;

Procedure InputPointsInMatrix(var FileInput: TextFile);
Var
    I, J: Integer;
    IsCorrect: Boolean;
Begin
    IsCorrect := True;
    With Form1 do
    Begin
        For I := 1 to StringGridPoints.ColCount - 1 do
        Begin
            For J := 1 to StringGridPoints.RowCount - 1 do
            Begin
                StringGridPoints.Cells[I, J] :=
                  TakeInformationIntoCell(FileInput, IsCorrect);
            End;
        End;
        ButtonSolve.Enabled := IsCorrect;
    End;
End;

procedure TForm1.N5Click(Sender: TObject);
var
    FileInput: TextFile;
begin
    If OpenDialog1.Execute Then
    Begin
        AssignFile(FileInput, OpenDialog1.FileName);
        Try
            Try
                Reset(FileInput);
                EditAmount.Text := GetSize(FileInput);
                if EditAmount.Text <> '' then
                Begin
                    ButtonPoints.Click;
                    InputPointsInMatrix(FileInput);
                End;
            Finally
                CloseFile(FileInput);
            End;
        Except

        End;
    End;
end;

Function Open(): String;
begin
    with Form1 Do
    begin
        If SaveDialog1.Execute Then
        begin
            Path := SaveDialog1.FileName;
            IsFileOpen := True;
        end
        Else
            IsFileOpen := False;
    end;
    Open := Path;
end;

procedure TForm1.N6Click(Sender: TObject);
var
    F: TextFile;
begin
    Path := Open;
    If IsFileOpen Then
    Begin
        AssignFile(F, Path);
        Rewrite(F);
        Writeln(F, Memo1.Text);
        Application.MessageBox('Данные успешно сохранены в файл',
          'Результат', 0);
        CloseFile(F);
    End;
end;

procedure TForm1.N8Click(Sender: TObject);
begin
    Form1.Close
end;

procedure TForm1.StringGridPointsKeyPress(Sender: TObject; var Key: Char);
begin
    If not(Key in ['0' .. '9', #8, #13]) Then
        Key := #0;
    if (Key = #13) And (ButtonSolve.Enabled = True) then
        ButtonSolve.Click
end;

procedure TForm1.StringGridPointsSetEditText(Sender: TObject;
  ACol, ARow: Integer; const Value: string);

var
    I, J: Integer;
    N: Integer;
    IsCorrect: Boolean;

begin
    For I := 1 to StringGridPoints.RowCount - 1 do
    Begin
        for J := 1 to StringGridPoints.ColCount - 1 do
        Begin
            IsCorrect := True;
            If StringGridPoints.Cells[I, J] <> '' Then
            Begin
                Try
                    N := StrToInt(StringGridPoints.Cells[I, J]);
                Except
                    StringGridPoints.Cells[I, J] := '';
                    Application.MessageBox
                      ('Проверьте корректность введенных данных', 'Ошибка', 0);
                    IsCorrect := False;
                End;
            End;

            If IsCorrect And (Length(StringGridPoints.Cells[I, J]) > 2) Then
            Begin
                StringGridPoints.Cells[I, J] := '';
                Application.MessageBox('Диапазон ввода [0; 99]', 'Ошибка', 0);
            End;
        End;
    End;

    For J := 1 to StringGridPoints.RowCount - 1 do
        for I := 1 to StringGridPoints.ColCount - 1 do
            If Length(StringGridPoints.Cells[I, J]) = 0 Then
                IsCorrect := False;
    ButtonSolve.Enabled := IsCorrect;
    Memo1.Clear;
    N6.Enabled := False
end;

end.