Pascal

program datasort;

{$mode objfpc}{$H+}{$J-}

uses
  SysUtils, Classes, Generics.Collections;
 
type
  TListInt = specialize TList<integer>;
 
var
  Numbers: TListInt;
  Num: integer;
 
begin
  Numbers := TListInt.Create();
  try
    Numbers.AddRange([1, 45, 78, 99, 32, 47]);
    Numbers.Sort;
 
    for Num in Numbers do
      WriteLn(Num);
  finally
    Numbers.Free;
  end;
end.

program jsonapi;

{$mode objfpc}{$H+}{$J-}

uses
  fpjson, jsonparser;

var
  JSON: TJSONObject;
begin
  JSON := GetJSON('{"name":"Alice","age":30}') as TJSONObject;
  try
    WriteLn(JSON.Get('name', ''), ' is ', JSON.Get('age', 0), ' years old');
  finally
    JSON.Free;
  end;
end.

program fileprocess;

{$mode objfpc}{$H+}{$J-}
 
 uses
   Classes, SysUtils, streamex;
 
 var
   FileStream: TFileStream;
   Reader: TStreamReader;
   Line: string;
   LineNum: integer;
 
 begin
   FileStream := TFileStream.Create('data.txt', fmOpenRead);
   try
     Reader := TStreamReader.Create(FileStream);
     try
       LineNum := 1;
       while not Reader.EOF do
       begin
         Line := Reader.ReadLine;
         WriteLn('Line ', LineNum, ': ', Line);
         Inc(LineNum);
       end;
     finally
       Reader.Free;
     end;
   finally
     FileStream.Free;
   end;
 end.

program sqlite;

{$mode objfpc}{$H+}{$J-}

uses
  SysUtils, sqldb, sqlite3conn;

var
  Conn: TSQLite3Connection;
  Query: TSQLQuery;
  Trans: TSQLTransaction;

begin
  Conn := TSQLite3Connection.Create(nil);
  Trans := TSQLTransaction.Create(nil);
  Query := TSQLQuery.Create(nil);
  try
    Conn.DatabaseName := 'users.db';
    Conn.Transaction := Trans;
    Trans.Database := Conn;
    Query.Database := Conn;
    Query.Transaction := Trans;
    
    Conn.Open;

    // Simple query
    Query.SQL.Text := 'SELECT name, age FROM users WHERE age > 25';
    Query.Open;

    while not Query.EOF do
    begin
      WriteLn(Query.FieldByName('name').AsString, ' is ',
              Query.FieldByName('age').AsInteger, ' years old');
      Query.Next;
    end;
  finally
    Query.Free;
    Trans.Free;
    Conn.Free;
  end;
end.

program csvparser;

{$mode objfpc}{$H+}{$J-}

uses
  SysUtils, csvdocument;

var
  CSV: TCSVDocument;
  Row, Col: Integer;

begin
  CSV := TCSVDocument.Create;
  try
    CSV.LoadFromFile('data.csv');

    WriteLn('CSV has ', CSV.RowCount, ' rows and ', CSV.ColCount[0], ' columns');
    WriteLn;

    for Row := 0 to CSV.RowCount - 1 do
    begin
      Write('Row ', Row + 1, ': ');
      for Col := 0 to CSV.ColCount[0] - 1 do
      begin
        Write(CSV.Cells[Col, Row]);
        if Col < CSV.ColCount[0] - 1 then Write(' | ');
      end;
      WriteLn;
    end;
  finally
    CSV.Free;
  end;
end.

program concurrent;

{$mode objfpc}{$H+}{$J-}

uses
  {$IFDEF UNIX}
  cthreads, cmem
  {$ENDIF}
  SysUtils, Classes, SyncObjs;

type
  TWorkerThread = class(TThread)
  private
    FTaskID: Integer;
  protected
    procedure Execute; override;
  public
    constructor Create(TaskID: Integer);
  end;

constructor TWorkerThread.Create(TaskID: Integer);
begin
  FTaskID := TaskID;
  inherited Create(False);
end;

procedure TWorkerThread.Execute;
begin
  WriteLn('Task ', FTaskID, ' starting...');
  Sleep(1000 + Random(2000)); // Simulate work
  WriteLn('Task ', FTaskID, ' completed!');
end;

var
  Threads: array[1..4] of TWorkerThread;
  i: Integer;

begin
  Randomize;

  // Start concurrent tasks
  for i := 1 to 4 do
    Threads[i] := TWorkerThread.Create(i);

  // Wait for completion
  for i := 1 to 4 do
  begin
    Threads[i].WaitFor;
    Threads[i].Free;
  end;

  WriteLn('All tasks completed!');
end.