45.pl

   1 #!/usr/bin/perl -w
   2
   3 use strict;
   4
   5 my $rounds;
   6 ($rounds, $_) = @ARGV;
   7
   8 while ($rounds--) {
   9         my ($cur) = /\A(.)/;
  10         do {
  11                 $cur--;
  12                 $cur = 9 if $cur == 0;
  13         } while (/\A.{1,3}$cur/);
  14
  15         s/\A(.)(...)(.*)$cur(.*)\z/$3$cur$2$4$1/;
  16         print $_, "\n";
  17 }
  18
  19 s/\A(.*)1(.*)\z/Result is $2$1\n/;
  20 print;