- Added solutions by Laurent Rosenfeld.

5 files changed, 115 insertions, 0 deletions

diff --git a/challenge-112/laurent-rosenfeld/blog.txt b/challenge-112/laurent-rosenfeld/blog.txt
new file mode 100644
index 0000000000..df8edd3267
--- /dev/null
+++ b/challenge-112/laurent-rosenfeld/blog.txt
@@ -0,0 +1 @@
+http://blogs.perl.org/users/laurent_r/2021/05/perl-weekly-challenge-112-canonical-path-and-climb-stairs.html
diff --git a/challenge-112/laurent-rosenfeld/perl/ch-1.pl b/challenge-112/laurent-rosenfeld/perl/ch-1.pl
new file mode 100644
index 0000000000..b118f809dd
--- /dev/null
+++ b/challenge-112/laurent-rosenfeld/perl/ch-1.pl
@@ -0,0 +1,21 @@
+use strict;
+use warnings;
+use feature "say";
+
+my @tests = ('/a/', '/a/b//c/', '/a/b/c/../..', '/a/../../b/', '/a/././b/');
+TEST: for my $path (@tests) {
+    my $p = $path;
+    $path =~ s|\/\/+|/|g;
+    $path =~ s!^\/|\/$!!g;
+    my @path_items;
+    for my $item (split /\/+/, $path) {
+        next if $item eq '.';
+        if ($item eq '..') {
+            warn "Invalid path $p" and next TEST unless @path_items;
+            pop @path_items;
+        } else {
+            push @path_items, $item;
+        }
+    };
+    say "$p => /", join '/', @path_items;
+}
diff --git a/challenge-112/laurent-rosenfeld/perl/ch-2.pl b/challenge-112/laurent-rosenfeld/perl/ch-2.pl
new file mode 100644
index 0000000000..c429de82e3
--- /dev/null
+++ b/challenge-112/laurent-rosenfeld/perl/ch-2.pl
@@ -0,0 +1,39 @@
+use strict;
+use warnings;
+use feature "say";
+
+my @result;
+
+sub print_result {
+    my $count = 0;
+    for  my $solution (@result) {
+        print "\tOption ", ++$count, ": ";
+        my @step_list;
+        push @step_list, "$_ " . ($_ =~ /1/ ? "step " : "steps") for @$solution;
+        say join " + ", @step_list;
+    }
+    say "";
+}
+
+sub try_steps  {
+    my ($nb_steps, $sum, @curr) = @_;
+    for my $new_step (1, 2) {
+        my $new_sum =  $sum + $new_step;
+        next if $new_sum > $nb_steps;
+        my @new_cur = (@curr, $new_step);
+        if ($new_sum == $nb_steps) {
+            push @result, \@new_cur;
+            last;
+        } else {
+            try_steps($nb_steps, $new_sum, @new_cur);
+        }
+    }
+}
+
+for my $target (3, 4, 5) {
+    @result = ();
+    try_steps $target, 0, ();
+    say 'Input: $n = ', $target;
+    say "Output: ", scalar @result;
+    print_result;
+}
diff --git a/challenge-112/laurent-rosenfeld/raku/ch-1.raku b/challenge-112/laurent-rosenfeld/raku/ch-1.raku
new file mode 100644
index 0000000000..f479cae6dd
--- /dev/null
+++ b/challenge-112/laurent-rosenfeld/raku/ch-1.raku
@@ -0,0 +1,19 @@
+use v6
+
+my @tests = </a/ /a/b//c/ /a/b/c/../.. /a/../../b/>;
+for @tests <-> $path {
+    my $p = $path;
+    $path ~~ s:g|'//'+|/|;
+    $path ~~ s:g!^'/' | '/'$!!;
+    my @path-items;
+    for split /'/'+/, $path -> $item {
+        next if $item eq '.';
+        if $item eq '..' {
+            die "Invalid path $p" unless @path-items;
+            pop @path-items;
+        } else {
+            push @path-items, $item;
+        }
+    };
+    say "$p => /", @path-items.join('/');
+}
diff --git a/challenge-112/laurent-rosenfeld/raku/ch-2.raku b/challenge-112/laurent-rosenfeld/raku/ch-2.raku
new file mode 100644
index 0000000000..e9cd8c5203
--- /dev/null
+++ b/challenge-112/laurent-rosenfeld/raku/ch-2.raku
@@ -0,0 +1,35 @@
+use v6;
+
+sub print-result {
+    my $count = 0;
+    for  @*result -> @solution {
+        print "\tOption ", ++$count, ": ";
+        my @step_list;
+        push @step_list, "$_ " ~ ($_ ~~ /1/ ?? "step " !! "steps") for @solution;
+        say join " + ", @step_list;
+    }
+    say "";
+}
+
+sub try-steps ($nb-steps, @curr) {
+    for 1, 2 -> $new-step {
+        my @new-cur = (|@curr, $new-step);
+        my $sum = [+] @new-cur;
+        next if $sum > $nb-steps;
+        if $sum == $nb-steps {
+            push @*result, @new-cur;
+            last;
+        } else {
+            try-steps $nb-steps, @new-cur;
+        }
+    }
+}
+
+for 3, 4, 5 -> $target {
+    my @*result;
+    try-steps $target, [];
+    say 'Input: $n = ', $target;
+    say "Output: ", @*result.elems;
+    # say @*result;
+    print-result;
+}