local fn IsPrime( n as NSUInteger ) as BOOL
  BOOL       isPrime = YES
  NSUInteger i

  if n < 2        then exit fn = NO
  if n = 2        then exit fn = YES
  if n mod 2 == 0 then exit fn = NO
  for i = 3 to int(n^.5) step 2
    if n mod i == 0 then exit fn = NO
  next
end fn = isPrime


local fn ReverseNumber( n as NSUInteger ) as NSUInteger
  NSInteger sum = 0

  if n < 10 then exit fn = n
  while ( n > 0 )
    sum = 10 * sum  + ( n mod 10 )
    n /= 10
  wend
end fn = sum


local fn IsEmirp( n as NSUInteger ) as BOOL
  BOOL result = NO
  NSUInteger r = fn ReverseNumber(n)
  if r != n and fn IsPrime(n) and fn IsPrime(r) then result = YES
end fn = result


local fn GetEmirpPrimes
  NSUInteger count = 0, i = 13

  printf @"\nThe first 20 Emirp primes are:"
  do
    if fn IsEmirp(i) then printf @"%4lu\b", i : count++
    i += 2
  until ( count == 20 )

  printf @"\n\nThe Emirp primes between 7700 and 8000 are:"
  i = 7701
  while ( i < 8000 )
    if fn IsEmirp(i) then printf @"%5lu\b", i
    i += 2
  wend

  i = 13 : count = 0
  while (1)
    if fn IsEmirp(i) then count++
    if count = 10000 then exit while
    i += 2
  wend
  printf @"\n\nThe 10,000th Emirp prime is: %lu", i

end fn

fn GetEmirpPrimes

HandleEvents