program quiz_program;
uses crt;

const Country: array[1..68] of string[26] = ('Brasil','Argentina','Bolivia','China',
   'Germany','Hungary','Israel','Italy','Japan','Kuwait','Costa Rica','Peru',
   'Portugal','Spain','Turkey','Belgium','Denmark','Norway','Sweden','Austria',
   'Bulgaria','Finland','Greece','Poland','Switzerland','Australia','Canada',
   'New Zealand','Egypt','Iran','El Savlador','Iraq','Lebanon','South Africa',
   'South Korea','Albania','Chile','Cuba','Malta','Oman','Seychelles','Sri Lanka',
   'Togo','Vietnam','Afghanistan','Burma','Scotland','England','Wales',
   'Northern Ireland','Republic of Ireland','United States of a America',
   'France','Holland','Romania','Russia','Mexico','Algeria','Fiji','Singapore',
   'Iceland','India','Indonesia','Jamaica','Panama','Thailand','Tunisia',
   'Jordon');

   Capital: array[1..68] of string[12] = ('Brasilia','Buenos Aires','La Paz','Peking',
   'Berlin','Budapest','Jerusalem','Rome','Tokyo','Kuwait','San Jos‚','Lima',
   'Lisbon','Madrid','Ankara','Brussels','Copenhagen','Olso','Stockholm','Vienna',
   'Sofia','Helsinki','Athens','Warsaw','Berne','Canberra','Ottawa','Wellington',
   'Cairo','Teheran','San Salvador','Baghdad','Beirut','Pretoria','Seoul',
   'Tirane','Santiago','Havana','Valletta','Muscat','Victoria','Colombo',
   'Lome','Hanoi','Kabul','Rangoon','Edinburgh','London','Cardiff','Belfast',
   'Dublin','Washington','Paris','Amsterdam','Bucharest','Moscow','Mexico City',
   'Algiers','Suva','Singapore','Reykjavik','New Delhi','Jakarta','Kingston',
   'Panama','Bangkok','Tunis','Amman');


   TermsQ: array[1..30] of string[5] = ('PC','RAM','ROM','CPU','DOS',
   'GUI','VDU','IBM','DTP','CAD','HTML','SVGA','ISP','GIF','UMB',
   'TSR','XMS','GIGO','BIOS','HMA','DLL','PCI','IDE','DDE','SCSI',
   'FAT','OLE','SIMM','MODEM','ISA');

   TermsA: array[1..30] of string[33] = ('Personal Computer',
   'Random Access Memory','Read Only Memory','Central Processing Unit',
   'Disk Operating System','Graphical User Interface',
   'Visual Display Unit','International Business Machines',
   'Desk Top Publishing','Computer Aided Design',

   'Hypertext Markup Language','Super Video Graphics Array',
   'Internet Service Provider','Graphics Interchange Format',
   'Upper Memory Block','Terminate Stay Resident',
   'Extended Memory','Garbage In Garbage Out',
   'Basic Input Output System','High Memory Area',

   'Dynamic Link Library','Peripheral Component Interconnect',
   'Integrated Drive Electronics','Dynamic Data Exchange',
   'Small Computer System Interface','File Allocation Table',
   'Object Linking And Embedding','Single Inline Memory Module',
   'Modulator Demodulator','Industry Standard Architecture');

type  pos_type = array[1..68] of boolean;
      temp_type = array[1..68] of integer;


procedure readxy(var reply : string;
                row,colour : integer);

procedure centre_line(reply : string;
                        row : integer;
                     letter : char);

var  column : integer;

begin
    window(1,row,80,row); clrscr;
    window(1,1,80,25);
    column := 40-(length(reply) div 2);
    if (not odd(length(reply))) and (letter=#13) then
       column := column + 1;
    gotoxy(column,row);
    write(reply);
end;


var  letter : char;
     count : integer;
     len : integer;

begin
   count := 1; reply := '';
   textcolor(colour);
   repeat
      letter := readkey;
      if letter=#8 then
      begin
         count := count - 1;
         if count < 1 then count := 1;
         write(chr(8),' ',chr(8));
         delete(reply,count,1);
         centre_line(reply,row,letter);
      end else
      begin
         count := count + 1;
         reply := reply + letter;
         centre_line(reply,row,letter);
      end;
   until letter=#13;
   len := length(reply);
   delete(reply,len,2);
end;

function uppercase(txt1 : string) : string;

var a : byte;

begin
    for a := 1 to length(txt1) do
      txt1[a] := upcase(txt1[a]);
    uppercase := txt1;
end;

procedure writexy(text1,text2,text3 : string;
                  row,colour : integer);

var  len,column : integer;
     tempstr : string;

begin
    tempstr := text1+text2+text3;
    len := length(tempstr);
    column := 40-(len div 2);
    gotoxy(column,row);
    textcolor(colour);
    write(tempstr);
    gotoxy(1,25);
end;

procedure display_menu(var option : integer;
                          var row : integer);

var  pause : char;

begin
   repeat

      clrscr;
      writexy('Select the quiz you want to play','','',10,6);
      writexy('Capital Cities','','',12,4);
      writexy('Computer Terms','','',13,4);
      writexy('Maths Quiz','','',14,4);
      writexy('Exit','','',15,4);
      textcolor(6);

      gotoxy(30,row);
      writeln(chr(175));

      gotoxy(49,row);
      writeln(chr(174));

      gotoxy(1,25);
      pause := readkey;
      case pause of
         #72 : row := row - 1;
         #80 : row := row + 1;
      end;

      if row < 12 then row := 12;
      if row > 15 then row := 15;

   until pause = #13;
   option := row;
   clrscr;
end;

procedure random_numbers(var rnd : integer;
                         var pos : pos_type;
                             max : integer);

var  ok : boolean;

begin
   ok := false;
   randomize;
   repeat
      rnd := random(max)+1;
      if pos[rnd] = false then
      begin
         ok := true;
         pos[rnd] := true;
      end
      else
         ok := false
   until ok;
end;

procedure ask_capital(var score : integer;
                            pos : pos_type;
                       var temp : temp_type);

var   answer : string;
      loop,rnd : integer;
      pause : char;

begin
   for loop := 1 to 10 do
   begin
      random_numbers(rnd,pos,68);
      temp[rnd] := temp[rnd] + 1;
      clrscr;

      writexy('What is the capital of ',country[rnd],'',10,6);
      readxy(answer,11,3);

      if answer = 'x' then break;
      if uppercase(answer) = uppercase(capital[rnd]) then
      begin
         inc(score);
         writexy('Correct answer','','',13,2);
         pause := readkey;
      end else
      begin
         writexy('Wrong answer','','',13,2);
         writexy('The correct answer is ',capital[rnd],'',14,4);
         pause := readkey;
      end;
   end;
end;

procedure ask_terms(var score : integer;
                          pos : pos_type);

var   answer : string;
      loop,rnd : integer;
      pause : char;

begin
   for loop := 1 to 10 do
   begin
      random_numbers(rnd,pos,30);
      clrscr;

      writexy('What does ',termsQ[rnd],' stand for',10,6);
      readxy(answer,11,3);

      if answer = 'x' then break;
      if uppercase(answer) = uppercase(termsA[rnd]) then
      begin
         inc(score);
         writexy('Correct answer','','',13,2);
         pause := readkey;
      end else
      begin
         writexy('Wrong answer','','',13,2);
         writexy('The correct answer is ',termsA[rnd],'',14,4);
         pause := readkey;
      end;
   end;
end;

procedure ask_sum(var score : integer);

var  num1,num2 : integer;
     reply : string;
     answer : string;
     loop : integer;
     pause : char;

begin
   randomize;
   for loop := 1 to 10 do
   begin
      clrscr;
      repeat
         num1 := random(20)+1;
         num2 := random(20)+1;
      until (num1>=5) and (num2>=5);

      gotoxy(32,10);
      textcolor(6);

      writeln('What is ',num1,' x ',num2);
      gotoxy(1,25);
      readxy(reply,11,3);
      str(num1*num2,answer);

      if reply = 'x' then break;
      if reply = answer then
      begin
         inc(score);
         writexy('Correct answer','','',13,2);
         pause := readkey;
      end else
      begin
         writexy('Wrong answer','','',13,2);
         writexy('The correct answer is ',answer,'',14,4);
         pause := readkey;
      end;
   end;
end;




procedure display_results(score : integer;
                       var temp : temp_type);

var rating,tempstr : string;
    pause : char;

begin
   clrscr;
   str(score,tempstr);
   writexy('You scored ',tempstr,' out of 10',10,6);

   case score of
      0..3 : rating := 'Poor ';
      4..6 : rating := 'Average';
      7..8 : rating := 'Very Good';
     9..10 : rating := 'Excellent';
   end;

   writexy('Rating = ',rating,'',11,2);
   writexy('Press the space bar to continue','','',13,4);

   repeat pause := readkey;
   until pause = #32;
end;


{  Start of main program  }


var   pos    : pos_type;
      score  : integer;
      option : integer;
      row    : integer;
      temp   : temp_type;

begin
   textmode(80);
   row := 12;
   while option <> 15 do
   begin
      score := 0;
      display_menu(option,row);
      case option of
         12 : ask_capital(score,pos,temp);
         13 : ask_terms(score,pos);
         14 : ask_sum(score);
      end;
      if option <> 15 then
      display_results(score,temp);
   end;
   textcolor(7);
   clrscr;
end.


{  End of main program  }