func damm inp$ .
   table[][] = [ [ 0 3 1 7 5 9 8 6 4 2 ] [ 7 0 9 2 1 5 4 8 6 3 ] [ 4 2 0 6 8 7 1 3 5 9 ] [ 1 7 5 0 9 8 3 4 2 6 ] [ 6 1 2 3 0 4 5 9 7 8 ] [ 3 6 7 4 2 0 9 5 8 1 ] [ 5 8 6 9 7 2 0 1 3 4 ] [ 8 9 4 5 3 6 2 0 1 7 ] [ 9 4 3 8 6 1 7 2 0 5 ] [ 2 5 8 1 4 3 6 7 9 0 ] ]
   inp[] = number strchars inp$
   for v in inp[]
      inter = table[inter + 1][v + 1]
   .
   return if inter = 0
.
nums[] = [ 5724 5727 112946 112949 ]
for v in nums[]
   write v & " is "
   if damm v = 1
      print "valid"
   else
      print "invalid"
   .
.