Praktikum 4 - Alpro 1 - Procedure Dan Function

Dibawah ini adalah script codenya :
program prosedur;
uses wincrt;
CONST
K='r1p4n1';
L='R1P4N1';
VAR M: STRING;
    N: INTEGER;
    User : String;

PROCEDURE BENAR;
BEGIN
IF (M=K) OR (M=L) THEN
BEGIN
CLRSCR;
WRITELN('Selamat Datang ', User ,'!');
WRITELN('Silakan Tekan Enter Untuk Memulai Program');
N:=3;
READLN;
END;
END;

PROCEDURE SALAH;
BEGIN
IF (M<>K) AND (M<>L) THEN
BEGIN
WRITELN;
WRITELN('Password Yang Anda Masukkan Salah!!');
WRITELN('        Silakan coba lagi!!');
N:=N+1;
END;
END;

PROCEDURE PERINGATAN;
BEGIN
IF N=2 THEN
BEGIN
CLRSCR;
WRITELN('Password Yang Anda Masukkan Salah!!');
WRITE('Ini kesempatan ketiga anda! Jika Password yang anda masukan salah lagi');
WRITELN(' maka program akan tidak berjalan lagi. Dan cobalah beberapa saat lagi!!');

END;
END;

PROCEDURE password;
BEGIN
N:=0;
REPEAT
Writeln;
WRITE('Masukkan Nama Anda = '); READLN(USER);
WRITE('Masukkan Password  = '); READLN(M);
BENAR;
SALAH;
PERINGATAN;
UNTIL N = 3;
end;



procedure Program1;
var
   a,b:integer;
   i:integer;
begin
    clrscr;
writeln('   Program Perulangan For');
writeln('---------------------------');
writeln;
write('1. Masukan indeks 1 = ');
readln(a);
write('2. Masukan indeks 2 = ');
readln(b);
writeln;
if a>b then for i:=a downto b do write ('',i)
else for i:=a to b do  write(' ',i);                
readln;
end;

procedure program2;
var
  i:integer;
  begin

  clrscr;
writeln('  Program Perulangan While Do');
writeln('--------------------------------');
begin    
i:=1;
   while(i<=20) do

   begin
writeln('Perulangan ke-',i);
   i:=i+1;
end;
readln;
   end;
   end;

var
  menu:integer;
  begin
  clrscr;
password;
repeat
clrscr;
writeln('----------------------------------');
writeln('----------------------------------');
writeln('------- ////////////////// -------');
writeln('------- // MENU PROGRAM // -------');
writeln('------- ////////////////// -------');
writeln('----------------------------------');
writeln('----------------------------------');
writeln;
writeln('1. Program Perulangan For ');
writeln('2. Program Perulangan While Do');
writeln('3. Exit');
writeln;
write('Masukan Kode Menu (1,2,3)= ');readln(Menu);
case menu of
1: program1;
2: program2;
3: exit;
end;
until menu =3;
end.