Merge pull request #2720 from PerlMonk-Athanasius/branch-for-challenge-085

Perl & Raku solutions to Tasks 1 & 2 of the Perl Weekly Challenge #085

4 files changed, 549 insertions, 0 deletions

diff --git a/challenge-085/athanasius/perl/ch-1.pl b/challenge-085/athanasius/perl/ch-1.pl
new file mode 100644
index 0000000000..d111d73169
--- /dev/null
+++ b/challenge-085/athanasius/perl/ch-1.pl
@@ -0,0 +1,148 @@
+#!perl
+
+###############################################################################
+=comment
+
+Perl Weekly Challenge 085
+=========================
+
+Task #1
+-------
+*Triplet Sum*
+
+Submitted by: Mohammad S Anwar
+
+You are given an array of real numbers greater than zero.
+
+Write a script to find if there exists a triplet (a,b,c) such that 1 < a+b+c <
+2. Print 1 if you succeed otherwise 0.
+
+Example 1:
+
+ Input: @R = (1.2, 0.4, 0.1, 2.5)
+ Output: 1 as 1 < 1.2 + 0.4 + 0.1 < 2
+
+Example 2:
+
+ Input: @R = (0.2, 1.5, 0.9, 1.1)
+ Output: 0
+
+Example 3:
+
+ Input: @R = (0.5, 1.1, 0.3, 0.7)
+ Output: 1 as 1 < 0.5 + 1.1 + 0.3 < 2
+
+=cut
+###############################################################################
+
+#==============================================================================
+=comment
+
+Assumption:
+A "triplet" is a *contiguous* sequence of 3 elements in the array.
+
+Note:
+If more than one triplet satisfies the requirement (and assuming $EXPLAIN is
+set to a true value), then only the first such triplet will be shown in the
+explanation.
+
+=cut
+#==============================================================================
+
+#--------------------------------------#
+# Copyright © 2020 PerlMonk Athanasius #
+#--------------------------------------#
+
+                                       # Exports:
+use strict;
+use warnings;
+use Const::Fast;                       # const()
+use Regexp::Common qw( number );       # %RE{num}
+
+const my $EXPLAIN => 1;
+const my $USAGE   =>
+"Usage:
+  perl $0 [<R> ...]
+
+    [<R> ...]    An array of real numbers greater than zero\n";
+
+#------------------------------------------------------------------------------
+BEGIN
+#------------------------------------------------------------------------------
+{
+    $| = 1;
+    print "\nChallenge 085, Task #1: Triplet Sum (Perl)\n\n";
+}
+
+#==============================================================================
+MAIN:
+#==============================================================================
+{
+    my @R = parse_command_line();
+
+    # Add zero to each real number to convert it to its decimal representation
+    # (where possible); e.g., 1e-4 --> 0.0001 but 1e-5 --> 1e-05
+
+    printf "Input:  \@R = (%s)\n", join ', ', map { $_ + 0 } @R;
+
+    if (my $index = search_for_triplet(\@R) < 0)   # -ve index means no triplet
+    {
+        print  "Output: 0\n";
+    }
+    elsif ($EXPLAIN)
+    {
+        my @triplet = @R[$index .. $index + 2];
+        my $sum     = 0;
+           $sum    += $_ for @triplet;
+
+        printf "Output: 1 as 1 < (%s = %f) < 2\n", join(' + ', @triplet), $sum;
+    }
+    else
+    {
+        print  "Output: 1\n";
+    }
+}
+
+#------------------------------------------------------------------------------
+sub search_for_triplet
+#------------------------------------------------------------------------------
+{
+    my ($R)  = @_;
+    my  $idx = -1;        # Array index of the first triplet element; -1 = none
+
+    if (scalar @$R >= 3)
+    {
+        for my $i (0 .. $#$R - 2)
+        {
+            my $sum = $R->[$i] + $R->[$i + 1] + $R->[$i + 2];
+
+            # Note: From Perl v5.32.0, this can be simplified to:
+            #       if (1 < $sum < 2)
+
+            if (1 < $sum && $sum < 2)
+            {
+                $idx = $i;
+                last;
+            }
+        }
+    }
+
+    return $idx;
+}
+
+#------------------------------------------------------------------------------
+sub parse_command_line
+#------------------------------------------------------------------------------
+{
+    for (@ARGV)
+    {
+        / \A $RE{num}{real} \z /x
+               or die qq[ERROR: "$_" is not a real number\n$USAGE];
+
+        $_ > 0 or die qq[ERROR: "$_" is not greater than zero\n$USAGE];
+    }
+
+    return @ARGV;
+}
+
+###############################################################################
diff --git a/challenge-085/athanasius/perl/ch-2.pl b/challenge-085/athanasius/perl/ch-2.pl
new file mode 100644
index 0000000000..d7dbadfd72
--- /dev/null
+++ b/challenge-085/athanasius/perl/ch-2.pl
@@ -0,0 +1,149 @@
+#!perl
+
+###############################################################################
+=comment
+
+Perl Weekly Challenge 085
+=========================
+
+Task #2
+-------
+*Power of Two Integers*
+
+Submitted by: Mohammad S Anwar
+
+You are given a positive integer $N.
+
+Write a script to find if it can be expressed as a ^ b where a > 0 and b > 1.
+Print 1 if you succeed otherwise 0.
+
+Example 1:
+
+ Input: 8
+ Output: 1 as 8 = 2 ^ 3
+
+Example 2:
+
+ Input: 15
+ Output: 0
+
+Example 3:
+
+ Input: 125
+ Output: 1 as 125 = 5 ^ 3
+
+=cut
+###############################################################################
+
+#--------------------------------------#
+# Copyright © 2020 PerlMonk Athanasius #
+#--------------------------------------#
+
+                                       # Exports:
+use strict;
+use warnings;
+use Const::Fast;                       # const()
+use Regexp::Common qw( number );       # %RE{num}
+
+const my $EXPLAIN => 1;
+const my $USAGE   =>
+"Usage:
+  perl $0 <N>
+
+    <N>    A positive integer\n";
+
+#------------------------------------------------------------------------------
+BEGIN
+#------------------------------------------------------------------------------
+{
+    $| = 1;
+    print "\nChallenge 085, Task #2: Power of Two Integers (Perl)\n\n";
+}
+
+#==============================================================================
+MAIN:
+#==============================================================================
+{
+    my $N = parse_command_line();
+
+    print "Input:  $N\n";
+
+    my ($base, $exp) = find_power($N);
+
+    if ($base < 1)
+    {
+        print "Output: 0\n";
+    }
+    elsif ($EXPLAIN)
+    {
+        print "Output: 1 as $N = $base ^ $exp\n";
+    }
+    else
+    {
+        print "Output: 1\n";
+    }
+}
+
+#------------------------------------------------------------------------------
+sub find_power
+#------------------------------------------------------------------------------
+{
+    my ($N)       = @_;
+    my  $base     = 0;
+    my  $exponent = 1;
+    my  $root     = round(sqrt $N);
+
+    if ($root * $root == $N)
+    {
+        $base     = $root;
+        $exponent = 2;
+    }
+    else
+    {
+        my $max_exp = round(log($N) / log(2));
+
+        for (my $exp = 3; $exp <= $max_exp; $exp += 2)
+        {
+               $root = round($N ** (1 / $exp));
+            my $n    = 1;
+               $n   *= $root for 1 .. $exp;
+
+            if ($n == $N)
+            {
+                $base     = $root;
+                $exponent = $exp;
+                last;
+            }
+        }
+    }
+
+    return ($base, $exponent);
+}
+
+#------------------------------------------------------------------------------
+sub round
+#------------------------------------------------------------------------------
+{
+    my ($n) = @_;
+
+    return int($n + 0.5);
+}
+
+#------------------------------------------------------------------------------
+sub parse_command_line
+#------------------------------------------------------------------------------
+{
+    my $args = scalar @ARGV;
+       $args == 1 or die qq[ERROR: Expected a single command-line ]  .
+                         qq[argument, found $args\n]                 . $USAGE;
+
+    my $N = $ARGV[0];
+       $N =~ / \A $RE{num}{int} \z /x
+                  or die qq[ERROR: "$N" is not an integer\n]         . $USAGE;
+
+       $N > 0     or die qq[ERROR: "$N" is not a positive integer\n] . $USAGE;
+
+    return int $N;
+}
+
+###############################################################################
diff --git a/challenge-085/athanasius/raku/ch-1.raku b/challenge-085/athanasius/raku/ch-1.raku
new file mode 100644
index 0000000000..68807ab604
--- /dev/null
+++ b/challenge-085/athanasius/raku/ch-1.raku
@@ -0,0 +1,128 @@
+use v6d;
+
+###############################################################################
+=begin comment
+
+Perl Weekly Challenge 085
+=========================
+
+Task #1
+-------
+*Triplet Sum*
+
+Submitted by: Mohammad S Anwar
+
+You are given an array of real numbers greater than zero.
+
+Write a script to find if there exists a triplet (a,b,c) such that 1 < a+b+c <
+2. Print 1 if you succeed otherwise 0.
+
+Example 1:
+
+ Input: @R = (1.2, 0.4, 0.1, 2.5)
+ Output: 1 as 1 < 1.2 + 0.4 + 0.1 < 2
+
+Example 2:
+
+ Input: @R = (0.2, 1.5, 0.9, 1.1)
+ Output: 0
+
+Example 3:
+
+ Input: @R = (0.5, 1.1, 0.3, 0.7)
+ Output: 1 as 1 < 0.5 + 1.1 + 0.3 < 2
+
+=end comment
+###############################################################################
+
+#--------------------------------------#
+# Copyright © 2020 PerlMonk Athanasius #
+#--------------------------------------#
+
+#==============================================================================
+=begin comment
+
+Assumption:
+A "triplet" is a *contiguous* sequence of 3 elements in the array.
+
+Note:
+If more than one triplet satisfies the requirement (and assuming $EXPLAIN is
+set to a true value), then only the first such triplet will be shown in the
+explanation.
+
+=end comment
+#==============================================================================
+
+my Bool constant $EXPLAIN = True;
+
+subset Positive of Real where * > 0;
+
+#------------------------------------------------------------------------------
+BEGIN
+#------------------------------------------------------------------------------
+{
+    "\nChallenge 085, Task #1: Triplet Sum (Raku)\n".put;
+}
+
+##=============================================================================
+sub MAIN
+(
+    *@R where .all ~~ Positive:D  #= An array of real numbers greater than zero
+)
+##=============================================================================
+{
+    # Add zero to each real number to convert it to its decimal representation
+    # (where possible); e.g., 0x10FE --> 4350 and 1e-4 --> 0.0001 but 1e-5 -->
+    # 1e-05
+
+    "Input:  @R = (%s)\n".printf: @R.map( { $_ + 0 } ).join: ', ';
+
+    if my Int $idx = search-for-triplet(@R) < 0    # -ve index means no triplet
+    {
+        "Output: 0".put;
+    }
+    elsif $EXPLAIN
+    {
+        my Positive @triplet = @R[$idx .. $idx + 2];
+
+        "Output: 1 as 1 < (%s = %f) < 2\n".printf:
+            @triplet.join(' + '), @triplet.sum;
+    }
+    else
+    {
+        "Output: 1".put;
+    }
+}
+
+#------------------------------------------------------------------------------
+sub search-for-triplet( Array:D[Positive:D] $R --> Int:D )
+#------------------------------------------------------------------------------
+{
+    my Int $idx = -1;     # Array index of the first triplet element; -1 = none
+
+    if $R.elems >= 3
+    {
+        for 0 .. $R.end - 2 -> UInt $i
+        {
+            if 1 < $R[$i .. $i + 2].sum < 2
+            {
+                $idx = $i;
+                last;
+            }
+        }
+    }
+
+    return $idx;
+}
+
+#------------------------------------------------------------------------------
+sub USAGE()
+#------------------------------------------------------------------------------
+{
+    my Str $usage = $*USAGE;
+
+    $usage ~~ s/ ($*PROGRAM-NAME) /raku $0/;
+    $usage.put;
+}
+
+##############################################################################
diff --git a/challenge-085/athanasius/raku/ch-2.raku b/challenge-085/athanasius/raku/ch-2.raku
new file mode 100644
index 0000000000..db68ff4174
--- /dev/null
+++ b/challenge-085/athanasius/raku/ch-2.raku
@@ -0,0 +1,124 @@
+use v6d;
+
+###############################################################################
+=begin comment
+
+Perl Weekly Challenge 085
+=========================
+
+Task #2
+-------
+*Power of Two Integers*
+
+Submitted by: Mohammad S Anwar
+
+You are given a positive integer $N.
+
+Write a script to find if it can be expressed as a ^ b where a > 0 and b > 1.
+Print 1 if you succeed otherwise 0.
+
+Example 1:
+
+ Input: 8
+ Output: 1 as 8 = 2 ^ 3
+
+Example 2:
+
+ Input: 15
+ Output: 0
+
+Example 3:
+
+ Input: 125
+ Output: 1 as 125 = 5 ^ 3
+
+=end comment
+###############################################################################
+
+#--------------------------------------#
+# Copyright © 2020 PerlMonk Athanasius #
+#--------------------------------------#
+
+my Bool constant $EXPLAIN = True;
+
+subset Positive of Int where * > 0;
+
+#------------------------------------------------------------------------------
+BEGIN
+#------------------------------------------------------------------------------
+{
+    "\nChallenge 085, Task #2: Power of Two Integers (Raku)\n".put;
+}
+
+##=============================================================================
+sub MAIN
+(
+    Positive:D $N                   #= A positive integer
+)
+##=============================================================================
+{
+    "Input:  $N".put;
+
+    my (UInt $base, Positive $exp) = find-power($N);
+
+    if $base == 0
+    {
+        "Output: 0".put;
+    }
+    elsif $EXPLAIN
+    {
+        "Output: 1 as $N = $base ^ $exp".put;
+    }
+    else
+    {
+        "Output: 1".put;
+    }
+}
+
+#------------------------------------------------------------------------------
+sub find-power( Positive:D $N --> List:D[UInt:D] )
+#------------------------------------------------------------------------------
+{
+    my UInt     $base     = 0;
+    my Positive $exponent = 1;
+    my Positive $root     = $N.sqrt.round;
+
+    if $root * $root == $N
+    {
+        $base     = $root;
+        $exponent = 2;
+    }
+    else
+    {
+        my UInt $max-exp = $N.log2.round;
+
+        loop (my UInt $exp = 3; $exp <= $max-exp; $exp += 2)
+        {
+            $root = ($N ** (1 / $exp)).round;
+
+            my UInt $n  = 1;
+                    $n *= $root for 1 .. $exp;
+
+            if $n == $N
+            {
+                $base     = $root;
+                $exponent = $exp;
+                last;
+            }
+        }
+    }
+
+    return [$base, $exponent];
+}
+
+#------------------------------------------------------------------------------
+sub USAGE()
+#------------------------------------------------------------------------------
+{
+    my Str $usage = $*USAGE;
+
+    $usage ~~ s/ ($*PROGRAM-NAME) /raku $0/;
+    $usage.put;
+}
+
+###############################################################################