-! Copyright (c) 2007-2008 Aaron Schaefer.
+! Copyright (c) 2007, 2008 Aaron Schaefer.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel math math.ranges sequences ;
IN: project-euler.006
-! Copyright (c) 2007-2008 Aaron Schaefer.
+! Copyright (c) 2007, 2008 Aaron Schaefer.
! See http://factorcode.org/license.txt for BSD license.
USING: kernel make math sequences sorting ;
IN: project-euler.009
-! Copyright (c) 2007-2008 Aaron Schaefer.
+! Copyright (c) 2007, 2008 Aaron Schaefer.
! See http://factorcode.org/license.txt for BSD license.
USING: math.functions project-euler.common sequences ;
IN: project-euler.016
-! Copyright (c) 2007-2008 Aaron Schaefer.
+! Copyright (c) 2007, 2008 Aaron Schaefer.
! See http://factorcode.org/license.txt for BSD license.
USING: ascii kernel math.ranges math.text.english sequences ;
IN: project-euler.017
-! Copyright (c) 2007-2008 Aaron Schaefer.
+! Copyright (c) 2007, 2008 Aaron Schaefer.
! See http://factorcode.org/license.txt for BSD license.
USING: math.combinatorics project-euler.common sequences ;
IN: project-euler.020
! Copyright (c) 2008 Aaron Schaefer.
! See http://factorcode.org/license.txt for BSD license.
-USING: kernel math math.parser math.ranges project-euler.common sequences ;
+USING: kernel math math.parser math.ranges project-euler.common sequences
+ strings ;
IN: project-euler.038
! http://projecteuler.net/index.php?section=problems&id=38
number>string dup reverse = ;
: pandigital? ( n -- ? )
- number>string natural-sort "123456789" = ;
+ number>string natural-sort >string "123456789" = ;
: pentagonal? ( n -- ? )
dup 0 > [ 24 * 1+ sqrt 1+ 6 / 1 mod zero? ] [ drop f ] if ;