var
  factorial: Uint64;
  n, z, i: integer;

begin
  write('n = '); readln(n);
  writeln('считаем факториал числа n-1');
  factorial := 1;
  for i := 2 to n - 1 do
    factorial := factorial * i;
  writeln('(n-1)! = ', factorial);
  begin
    writeln('проверяем:');
    z := factorial + 1;
    if z mod n = 0 then  writeln('остаток = 0 => n - простое число')
    else
    begin
      writeln('остаток ≠0 => n - составное число');
      
    end;
  end;
end.

var
  factorial: QWord;
  n, i: integer;

begin
 Repeat
  write('n (0 to exit) = ');
  readln(n);
  if n>0 then
   begin
    factorial := 1;
    for i := 2 to n - 1 do
     factorial := factorial * i;
    writeln('(n-1)! = ', factorial);
    writeln('testing:');
    if ((factorial+1) mod n)=0 then
     writeln('n is prime')
    else
     writeln('n is composite');
   end;
 Until n=0;
end.

var
 z,p,m:QWord;
 n,i:integer;

begin
 Repeat
  write('n (0 to exit) = ');
  readln(n);
  if n>0 then
   begin
    z:=1;
    i:=1;
    p:=1;
    repeat
     inc(i);
     z:=z*i;
     if (z mod 10)=0 then
      begin
       z:=z div 10;
       p:=p*10;
      end;
    until i=n-1;
    m:=((z mod n)*p) mod n;
    writeln('testing:');
    if m=n-1 then
     writeln('n is prime')
    else
     writeln('n is composite');
   end;
 Until n=0;
end.