Merge pull request #1126 from noudald/challenge-042-noud

Challenge 042 noud

2 files changed, 69 insertions, 0 deletions

diff --git a/challenge-042/noud/perl6/ch-1.p6 b/challenge-042/noud/perl6/ch-1.p6
new file mode 100644
index 0000000000..21c3deec02
--- /dev/null
+++ b/challenge-042/noud/perl6/ch-1.p6
@@ -0,0 +1,18 @@
+# Octal Number System
+#
+# Write a script to print decimal number 0 to 50 in Octal Number System.
+#
+# For example:
+# Decimal 0 = Octal 0
+# Decimal 1 = Octal 1
+# Decimal 2 = Octal 2
+# Decimal 3 = Octal 3
+# Decimal 4 = Octal 4
+# Decimal 5 = Octal 5
+# Decimal 6 = Octal 6
+# Decimal 7 = Octal 7
+# Decimal 8 = Octal 10
+#
+# and so on.
+
+say $_.fmt("Decimal $_ = Octal %o") for ^51;
diff --git a/challenge-042/noud/perl6/ch-2.p6 b/challenge-042/noud/perl6/ch-2.p6
new file mode 100644
index 0000000000..59415fbd69
--- /dev/null
+++ b/challenge-042/noud/perl6/ch-2.p6
@@ -0,0 +1,51 @@
+# Balanced Brackets
+#
+# Write a script to generate a string with random number of ( and ) brackets.
+# Then make the script validate the string if it has balanced brackets.
+#
+# For example:
+# () - OK
+# (()) - OK
+# )( - NOT OK
+# ())() - NOT OK
+
+sub rand_brackets($size) {
+    return [~] (<( )>.pick() for ^$size);
+}
+
+sub balanced($brackets) {
+    # Count the open ( and close ) brackets sequentially. ( is given +1, ) is
+    # given -1. If the count ever goes below zero there are more close
+    # brackets than open brackets, hence an unbalanced string. If at the end
+    # the count is more than zero there are more open brackets than close
+    # brackets, hence an unbalanced string.
+    my $c = 0;
+
+    for $brackets.comb() -> $b {
+        if ($b === '(') {
+            $c++;
+        } elsif (--$c < 0) {
+            return False;
+        }
+    }
+
+    return $c == 0;
+}
+
+say "()    - " ~ balanced("()");
+say "(())  - " ~ balanced("(())");
+say ")(    - " ~ balanced(")(");
+say "())() - " ~ balanced("())()");
+
+
+my $brackets = '';
+for 1..20 -> $i {
+    # Only generate bracket strings of length 4, because with higher lengths
+    # the randomly generated strings rarely are balanced.
+    $brackets = rand_brackets(4);
+    if (balanced($brackets)) {
+        say $brackets ~ ' is balanced.';
+    } else {
+        say $brackets ~ ' is not balanced.';
+    }
+}