- Added solutions by Ulrich Rieke.

2 files changed, 122 insertions, 0 deletions

diff --git a/challenge-064/ulrich-rieke/perl/ch-1.pl b/challenge-064/ulrich-rieke/perl/ch-1.pl
new file mode 100644
index 0000000000..eb597d9f9c
--- /dev/null
+++ b/challenge-064/ulrich-rieke/perl/ch-1.pl
@@ -0,0 +1,103 @@
+#!/usr/bin/perl ;
+use strict ;
+use warnings ;
+use Algorithm::Combinatorics qw ( variations_with_repetition ) ;
+
+sub enterArray {
+  my $columns = shift ;
+  my $rows = shift ;
+  my $rowcount = 0 ;
+  my @array ;
+  while ( $rowcount != $rows ) {
+      print "Enter $columns integers, separated by space!\n" ;
+      my $input = <STDIN> ;
+      chomp $input ;
+      while ( scalar ( split ( /\s+/ , $input ) ) != $columns ) {
+    print "Not enough columns entered! Please repeat entry!\n" ;
+    $input = <STDIN> ;
+    chomp $input ;
+      }
+      my @line = split ( /\s+/ , $input ) ;
+      push ( @array , \@line ) ;
+      $rowcount++ ;
+  }
+  return @array ;
+}
+
+#we have to create different paths through the number array.
+#we can do that by defining rightways shifts for every different row.
+#to arrive at the right lower point, the rightward shifts in every row
+#have to add up to the number of columns.
+#I numbered the columns from 0 to columns - 1.
+#by creating "variations with repetitions" with as many elements as rows
+#and selecting those that add up to the number of columns I get
+#combinations of shifts per row that lead to the right lower corner
+sub createPaths {
+  my $columns = shift ;
+  my $rows = shift ;
+  my @onerow = (0..$columns - 1) ;
+  my @possibleCombis ;
+  my $iter = variations_with_repetition( \@onerow, $rows ) ;
+  while ( my $p = $iter->next ) {
+      if ( sumUpArray( $p ) == $columns - 1 ) {
+    push( @possibleCombis, $p ) ;
+      }
+  }
+  return @possibleCombis ;
+}
+
+sub sumUpArray {
+  my $array = shift ;
+  my $sum = 0 ;
+  for my $i ( @{$array} ) {
+      $sum += $i ;
+  }
+  return $sum ;
+}
+
+#the number array and the list of shift combinations per row are taken
+#in as parameters. We then go through the array and pick up numbers on
+#the way
+sub findPath {
+  my $numbers = shift ;
+  my $path = shift ;
+  my @nums ;
+  my @array = @{$numbers} ;
+  my $currentcolumn = 0 ;
+  my $currentrow = 0 ;
+  while ( @{$path} ) {
+      my $howmany = shift @{$path} ;
+      if ( $howmany > 0 ) {
+    push( @nums , @{$array[ $currentrow ] }[ $currentcolumn..
+    $currentcolumn + $howmany]) ;
+    $currentcolumn += $howmany ;
+      }
+      else {
+    push( @nums , ${$array[ $currentrow ]}[$currentcolumn] ) ;
+      }
+      $currentrow++ ;
+  }
+  return @nums ;
+}
+
+print "How many columns ?\n" ;
+my $columns = <STDIN> ;
+chomp $columns ;
+print "How many rows ?\n" ;
+my $rows = <STDIN> ;
+chomp $rows ;
+my @numbers = enterArray( $columns , $rows ) ;
+my @combis = createPaths( $columns, $rows ) ;
+my $minsum = 1000000 ;
+my @minpath ;
+foreach my $c ( @combis ) {
+  my @nums = findPath( \@numbers , $c ) ;
+  my $sum = sumUpArray( \@nums ) ;
+  if ( $sum < $minsum ) {
+      $minsum = $sum ;
+      @minpath = @nums ;
+  }
+}
+print "$minsum(" ;
+print join ( '->' , @minpath ) ;
+print ")\n" ;
diff --git a/challenge-064/ulrich-rieke/perl/ch-2.pl b/challenge-064/ulrich-rieke/perl/ch-2.pl
new file mode 100644
index 0000000000..53977cdd89
--- /dev/null
+++ b/challenge-064/ulrich-rieke/perl/ch-2.pl
@@ -0,0 +1,19 @@
+#!/usr/bin/perl ;
+use strict ;
+use warnings ;
+
+my $S = $ARGV[0] ;
+my @W = ( "weekly" , "challenge" , "perl" ) ;
+my @found ;
+for my $word ( @W ) {
+  if ( $S =~ /$word/ ) {
+      push( @found , $word ) ;
+  }
+}
+if ( @found ) {
+  print join( ',' , @found ) ;
+  print "\n" ;
+}
+else {
+  print "0 as none matching word found.\n" ;
+}