HEADLINE
The much awaited event, **Conference in the Cloud” took most of my free time. Having said that I still managed to do Live Coding YouTube videosfor Divide Integers and Power Integers.
I really enjoyed both tasks, specially Power Integers. It didn’t take long to solve both tasks. I was able to get it done by midweek. But for YouTube video, I had to wait until the conference was over. Thanks to the Chief Editor of Perl Weekly newletter editorial note, I now have 67 subscribers to my YouTube Channel. I would like to thank each and every subscriber. I promise to do regular video every week.
Let me share my solutions to the Perl Weekly Challenge - 066.
TASK #1 › Divide Integers
Submitted by Mohammad S Anwar
You are given two integers $M and $N.
Write a script to divide the given two integers i.e. $M / $N without using multiplication, division and mod operator and return the floor of the result of the division.
For the first task Divide Integers, I created sub natural_div() as below. It does everything that is required for this task. As per thr tradition that I follow generally, I started with standard parameter checking. Based on the example, I had to deal with the signs as well.
sub natural_div {
my ($m, $n) = @_;
die "ERROR: Missing dividend.\n" unless defined $m;
die "ERROR: Missing divisor.\n" unless defined $n;
die "ERROR: Dividend > Divisor [$m / $n].\n" unless abs($m) > abs($n);
die "ERROR: Invalid divisor [$n], can't be 0.\n" if $n == 0;
my $sign = '';
if ($m < 0) {
$sign = '-' if ($n > 0);
}
else {
$sign = '-' if ($n < 0);
}
my $abs_m = abs($m);
my $abs_n = abs($n);
my $i = 0;
for ($i = 0; $abs_m >= $abs_n; $i++) {
$abs_m -= $abs_n;
}
$i++ if ($sign ne '');
return sprintf("%s%d", $sign, $i);
}
Standard Perl to Raku translation and we have sub natural-div().
sub natural-div(Int $m, Int $n where $n != 0) {
my $sign = '';
if $m < 0 {
$sign = '-' if $n > 0;
}
else {
$sign = '-' if $n < 0;
}
my $abs_m = abs($m);
my $abs_n = abs($n);
my $i = 0;
for 0 .. $abs_n {
last if $abs_m <= $abs_n;
$abs_m -= $abs_n;
$i++;
}
$i++ if $sign ne '';
return sprintf("%s%d", $sign, $i);
}
Perl standalone app using the sub natural_div().
use strict;
use warnings;
my $M = $ARGV[0];
my $N = $ARGV[1];
print sprintf("%d / %d = %s\n", $M, $N, natural_div($M, $N));
Similar Raku app using the sub natural-div(),
use v6.d;
sub MAIN(Int :$M = -5, Int :$N where { $N != 0 } = 2) {
say sprintf("%d / %d = %s", $M, $N, natural-div($M, $N));
}
Completed with unit test as below.
use strict;
use warnings;
use POSIX;
use Test::More;
is (natural_div( 5, 2), floor( 5 / 2), ' 5 / 2 = 2');
is (natural_div(-5, 2), floor(-5 / 2), '-5 / 2 = -3');
is (natural_div(-5, -2), floor(-5 / -2), '-5 / -2 = 2');
done_testing;
Along with Raku unit test.
use Test;
is natural-div( 5, 2), 2, ' 5 / 2 = 2';
is natural-div(-5, 2), -3, '-5 / 2 = -3';
is natural-div(-5, -2), 2, '-5 / -2 = 2';
done-testing;
TASK #2 › Power Integers
Submitted by Mohammad S Anwar
You are given an integer $N.
Write a script to check if the given number can be expressed as mn where m and n are positive integers. Otherwise print 0.
Please make sure m > 1 and n > 1.
BONUS: If there are more than one ways to express the given number then print all possible solutions.
Below is the sub get_power_integers() returns all possible solutions.
sub get_power_integers {
my ($n) = @_;
my $power_integers = [];
my $i = 2;
while ( $i <= sqrt($n) ) {
my $j = 2;
while ( $j <= $n ) {
if (($i ** $j) == $n) {
push @$power_integers, sprintf("%d ^ %d", $i, $j);
}
$j++;
}
$i++;
}
$power_integers = [0] unless scalar(@$power_integers);
return $power_integers;
}
Doing Raku version was fun as you can see below.
sub get-power-integers(Int $n where { $n > 1 }) {
my $power_integers = [];
my $i = 2;
while $i <= sqrt($n) {
my $j = 2;
while $j <= $n {
if ($i ** $j) == $n {
$power_integers.push: sprintf("%d ^ %d", $i, $j);
}
$j++;
}
$i++;
}
return $power_integers if $power_integers.elems > 0;
return 0;
}
Perl app for the Power Integers task.
use strict;
use warnings;
my $N = $ARGV[0];
print sprintf("%d = %s\n", $N, join(", ", @{get_power_integers($N)}));
Similar Raku app for the same task.
use Test;
is sprintf("%d = %s", 9, get-power-integers(9).join(", ")),
'9 = 3 ^ 2',
'9 = 3 ^ 2';
is sprintf("%d = %s", 45, get-power-integers(45).join(", ")),
'45 = 0',
'45 = 0';
is sprintf("%d = %s", 64, get-power-integers(64).join(", ")),
'64 = 2 ^ 6, 4 ^ 3, 8 ^ 2',
'64 = 2 ^ 6, 4 ^ 3, 8 ^ 2';
done-testing;
Perl unit test.
use strict;
use warnings;
use Test::More;
use Test::Deep;
is_deeply(get_power_integers(9),
['3 ^ 2'],
' 9 = 3 ^ 2');
is_deeply(get_power_integers(45),
[ 0 ],
'45 = 0');
is_deeply(get_power_integers(64),
['2 ^ 6', '4 ^ 3', '8 ^ 2'],
'64 = 2 ^ 6, 4 ^ 3, 8 ^ 2');
done_testing;
Finally Raku unit test in the end.
use Test;
is sprintf("%d = %s", 9, get-power-integers(9).join(", ")),
'9 = 3 ^ 2',
'9 = 3 ^ 2';
is sprintf("%d = %s", 45, get-power-integers(45).join(", ")),
'45 = 0',
'45 = 0';
is sprintf("%d = %s", 64, get-power-integers(64).join(", ")),
'64 = 2 ^ 6, 4 ^ 3, 8 ^ 2',
'64 = 2 ^ 6, 4 ^ 3, 8 ^ 2';
done-testing;
That’s it for this week. Speak to you soon.