Merge pull request #9213 from LubosKolouch/master

Challenge 246 LK Perl Python Raku blog

7 files changed, 170 insertions, 0 deletions

diff --git a/challenge-246/lubos-kolouch/blog.txt b/challenge-246/lubos-kolouch/blog.txt
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+++ b/challenge-246/lubos-kolouch/blog.txt
@@ -0,0 +1 @@
+https://egroup.kolouch.org/nextcloud/sites/lubos/2023-12-04_Weekly_challenge_246
diff --git a/challenge-246/lubos-kolouch/perl/ch-1.pl b/challenge-246/lubos-kolouch/perl/ch-1.pl
new file mode 100644
index 0000000000..c9e7b2c514
--- /dev/null
+++ b/challenge-246/lubos-kolouch/perl/ch-1.pl
@@ -0,0 +1,21 @@
+use strict;
+use warnings;
+use List::Util 'shuffle';
+
+sub pick_lotto_numbers {
+    my @numbers = ( 1 .. 49 );
+    my @picked  = ( shuffle @numbers )[ 0 .. 5 ];
+    return @picked;
+}
+
+# Test
+use Test::More tests => 1;
+my @result = sort { $a <=> $b } pick_lotto_numbers();
+is( scalar(@result), 6, 'Six numbers are picked' );
+
+# Additional tests to check uniqueness and range can be added
+
+# Main
+foreach my $num ( sort { $a <=> $b } pick_lotto_numbers() ) {
+    print "$num\n";
+}
diff --git a/challenge-246/lubos-kolouch/perl/ch-2.pl b/challenge-246/lubos-kolouch/perl/ch-2.pl
new file mode 100644
index 0000000000..769b287936
--- /dev/null
+++ b/challenge-246/lubos-kolouch/perl/ch-2.pl
@@ -0,0 +1,38 @@
+use strict;
+use warnings;
+
+sub is_linear_recurrence {
+    my @a = @_;
+
+    # Need at least 5 elements to form two equations and solve for p and q
+    return 0 if @a < 5;
+
+    # Forming two equations:
+    # a[2] = p * a[0] + q * a[1]
+    # a[3] = p * a[1] + q * a[2]
+    # And solving for p and q
+    my $denominator = $a[0] * $a[2] - $a[1]**2;
+    return 0 if $denominator == 0;    # Avoid division by zero
+
+    my $p = ( $a[2] * $a[3] - $a[1] * $a[4] ) / $denominator;
+    my $q = ( $a[4] - $p * $a[2] ) / $a[3];
+
+    # Check if p and q are integers
+    return 0 if $p != int($p) || $q != int($q);
+
+    # Verify the recurrence for the rest of the array
+    for my $i ( 4 .. $#a ) {
+        return 0 if $a[$i] != $p * $a[ $i - 2 ] + $q * $a[ $i - 1 ];
+    }
+
+    return 1;
+}
+
+# Tests
+use Test::More tests => 3;
+ok( is_linear_recurrence( 1,  1, 2, 3,  5 ), 'Fibonacci sequence' );
+ok( !is_linear_recurrence( 4, 2, 4, 5,  7 ), 'Even-odd mismatch' );
+ok( is_linear_recurrence( 4,  1, 2, -3, 8 ), 'Custom sequence' );
+
+# Main
+print is_linear_recurrence( 4, 1, 2, -3, 8 ) ? "true\n" : "false\n";
diff --git a/challenge-246/lubos-kolouch/python/ch-1.py b/challenge-246/lubos-kolouch/python/ch-1.py
new file mode 100644
index 0000000000..7428e5f573
--- /dev/null
+++ b/challenge-246/lubos-kolouch/python/ch-1.py
@@ -0,0 +1,29 @@
+#!/usr/bin/env python
+
+import random
+from typing import List
+
+
+def pick_lotto_numbers() -> list[int]:
+    return random.sample(range(1, 50), 6)
+
+
+# Test
+import unittest
+
+
+class TestLottoNumbers(unittest.TestCase):
+    def test_lotto_numbers(self):
+        result = pick_lotto_numbers()
+        self.assertEqual(len(result), 6)
+        self.assertEqual(len(set(result)), 6)
+        for num in result:
+            self.assertTrue(1 <= num <= 49)
+
+
+if __name__ == "__main__":
+    unittest.main()
+
+# Main
+for num in sorted(pick_lotto_numbers()):
+    print(num)
diff --git a/challenge-246/lubos-kolouch/python/ch-2.py b/challenge-246/lubos-kolouch/python/ch-2.py
new file mode 100644
index 0000000000..59a6157385
--- /dev/null
+++ b/challenge-246/lubos-kolouch/python/ch-2.py
@@ -0,0 +1,38 @@
+#!/usr/bin/env python
+
+import numpy as np
+
+
+def is_linear_recurrence(a):
+    if len(a) < 5:
+        return False
+
+    # Forming matrix to solve the linear equations
+    A = np.array([[a[0], a[1]], [a[1], a[2]]])
+    B = np.array([a[2], a[3]])
+
+    # Solve for p and q
+    try:
+        p, q = np.linalg.solve(A, B)
+    except np.linalg.LinAlgError:
+        return False  # Cannot solve if the matrix A is singular
+
+    # Check if p and q are integers
+    if not (p.is_integer() and q.is_integer()):
+        return False
+
+    # Verify the recurrence for the rest of the array
+    for i in range(4, len(a)):
+        if a[i] != int(p) * a[i - 2] + int(q) * a[i - 1]:
+            return False
+
+    return True
+
+
+# Tests
+assert is_linear_recurrence([1, 1, 2, 3, 5]) == True, "Fibonacci sequence"
+assert is_linear_recurrence([4, 2, 4, 5, 7]) == False, "Even-odd mismatch"
+assert is_linear_recurrence([4, 1, 2, -3, 8]) == True, "Custom sequence"
+
+# Main
+print("true" if is_linear_recurrence([4, 1, 2, -3, 8]) else "false")
diff --git a/challenge-246/lubos-kolouch/raku/ch-1.raku b/challenge-246/lubos-kolouch/raku/ch-1.raku
new file mode 100644
index 0000000000..9172978212
--- /dev/null
+++ b/challenge-246/lubos-kolouch/raku/ch-1.raku
@@ -0,0 +1,13 @@
+sub pick-lotto-numbers() {
+    return (1..49).roll(*).unique.head(6);
+}
+
+# Test
+use Test;
+plan 1;
+my @result = pick-lotto-numbers().sort;
+is @result.elems, 6, 'Six numbers are picked';
+# Additional tests for uniqueness and range can be added
+
+# Main
+.say for pick-lotto-numbers().sort;
diff --git a/challenge-246/lubos-kolouch/raku/ch-2.raku b/challenge-246/lubos-kolouch/raku/ch-2.raku
new file mode 100644
index 0000000000..ae2a0de1df
--- /dev/null
+++ b/challenge-246/lubos-kolouch/raku/ch-2.raku
@@ -0,0 +1,30 @@
+sub is-linear-recurrence(@a) {
+    return False if @a.elems < 5;
+
+    # Solving for p and q using the first four elements
+    my $denominator = @a[0] * @a[2] - @a[1]**2;
+    return False if $denominator == 0;  # Avoid division by zero
+
+    my $p = (@a[2] * @a[3] - @a[1] * @a[4]) / $denominator;
+    my $q = (@a[4] - $p * @a[2]) / @a[3];
+
+    # Check if p and q are integers
+    return False if $p != $p.Int || $q != $q.Int;
+
+    # Verify the recurrence for the rest of the array
+    for 4..^@a.elems -> $i {
+        return False if @a[$i] != $p.Int * @a[$i-2] + $q.Int * @a[$i-1];
+    }
+
+    return True;
+}
+
+# Tests
+use Test;
+plan 3;
+ok is-linear-recurrence([1, 1, 2, 3, 5]), 'Fibonacci sequence';
+ok !is-linear-recurrence([4, 2, 4, 5, 7]), 'Even-odd mismatch';
+ok is-linear-recurrence([4, 1, 2, -3, 8]), 'Custom sequence';
+
+# Main
+say is-linear-recurrence([4, 1, 2, -3, 8]) ?? "true" !! "false";