diff --git a/challenge-059/cheok-yin-fung/BLOG.txt b/challenge-059/cheok-yin-fung/BLOG.txt new file mode 100644 index 0000000000..0db37b7d91 --- /dev/null +++ b/challenge-059/cheok-yin-fung/BLOG.txt @@ -0,0 +1 @@ +http://blogs.perl.org/users/c_y_fung/2020/05/cys-take-on-perl-weekly-challenge-059.html diff --git a/challenge-059/cheok-yin-fung/perl/ch-1.pl b/challenge-059/cheok-yin-fung/perl/ch-1.pl new file mode 100644 index 0000000000..64e34adbb2 --- /dev/null +++ b/challenge-059/cheok-yin-fung/perl/ch-1.pl @@ -0,0 +1,121 @@ +#!/usr/bin/perl +use strict; + +{ package item; + + sub new + { + my ($class) = @_; + bless { + _value => $_[1], + _next => $_[2], + }, $class; + } + + sub value { $_[0]->{_value}} + + sub inext { + my ($self, $newnext) = @_; + $self->{_next} = $newnext if defined($newnext); + return $self->{_next}; + } + + sub unlink { + my ($self) = @_; + $self->{_next} = undef; + return $self->{_next}; + } +} + +#my @input = (2,1, 2,3); +#my $K = 2; + +my @input = (5,6,3,2,7,9); +my $K = 6; + +#my @input = (1 , 4, 3, 2, 5, 2 ); +#my $K = 3; + +# my @input = (2 , 4, 3, 1, 5, 1 ); + # my $K = 3; + +my ($head, $smallpivot, $inusepivot); +my $ll; + + +sub make_linked_list { + my @temp_list = @_; + $ll->[$#temp_list] = item->new( $temp_list[$#temp_list] , \(undef) ); + for (reverse 0..$#temp_list-1) { + $ll->[$_] = item->new($temp_list[$_] , \( $ll->[$_+1] ) ); + } + $head = \($ll->[0]); +} + + + +my $HELPER = -1; +make_linked_list($HELPER, @input); + +$smallpivot = $head; +$inusepivot = ${$head}->inext; + +sub print_linked_listi { #for testing use + my $i = 0; + my $t = ${$head}; + while( $t = ${$t->inext} and $i<10) { + print $t->value, "->"; + $i++; + } + print "nil\n"; +} + +sub print_linked_list { + my $t = ${$head}; + while( $t = ${$t->inext} ) { + print $t->value, "->"; + } + print "nil\n"; +} + + +print "\nbefore: "; +print_linked_list; +print "\n"; + +my $j = 0; + +my $previous = $head; +while( 1) { #j is for testing help + + # print $$inusepivot->value, " " ,$$smallpivot->value, " \n"; + # print_linked_list;print "\n"; + + if ($$inusepivot->value < $K) { + $$previous->unlink; + $$previous->inext( $$inusepivot->inext ); + + $$inusepivot->unlink; + $$inusepivot->inext($$smallpivot->inext); + + $$smallpivot->unlink; + $$smallpivot->inext($inusepivot); + $smallpivot = $inusepivot; + + } + + + if (($$previous->inext != \undef) and ($$inusepivot->inext != \undef)) { + $previous = $inusepivot; + $inusepivot = $$inusepivot->inext; + } + else { + print "\nafter : "; + print_linked_list; + exit; + } + +} + + + diff --git a/challenge-059/cheok-yin-fung/perl/ch-2.pl b/challenge-059/cheok-yin-fung/perl/ch-2.pl new file mode 100644 index 0000000000..420c20d172 --- /dev/null +++ b/challenge-059/cheok-yin-fung/perl/ch-2.pl @@ -0,0 +1,31 @@ +#!/usr/bin/perl +use strict; +use Test::Simple tests => 2; +use List::Util qw/max sum/; + +#reference: https://www.tutorialspoint.com/perl/bitwise_operators_example.htm + + +sub f { # compare two bit-strings by xor + my $hint = ($_[0] ^ $_[1]) ; + my $ans = sum (split //, sprintf("%b", $hint)); + return $ans; +} + +# first parameter: number of terms; remaining: terms in the list +sub conclude { + my ($N, @val) = @_; + my $sum = 0; + for my $i (0..$N-2) { + for my $j ($i+1..$N-1) { + $sum += f($val[$i], $val[$j]); + } + } + return $sum; +} + + +ok (conclude(3,2,3,4) == 6), "bad"; +ok (conclude(2,1,3)==1), "too bad"; + +