Add Python solution to challenge 148

5 files changed, 113 insertions, 17 deletions

diff --git a/challenge-148/paulo-custodio/perl/ch-1.pl b/challenge-148/paulo-custodio/perl/ch-1.pl
index 2a0ce52919..9dd13818c2 100644
--- a/challenge-148/paulo-custodio/perl/ch-1.pl
+++ b/challenge-148/paulo-custodio/perl/ch-1.pl
@@ -2,11 +2,11 @@
 
 # Challenge 148
 #
-# TASK #1 › Eban Numbers
+# TASK #1 > Eban Numbers
 # Submitted by: Mohammad S Anwar
 # Write a script to generate all Eban Numbers <= 100.
 #
-# An Eban number is a number that has no letter ‘e’ in it when the number
+# An Eban number is a number that has no letter 'e' in it when the number
 # is spelled in English (American or British).
 #
 # Example
diff --git a/challenge-148/paulo-custodio/perl/ch-2.pl b/challenge-148/paulo-custodio/perl/ch-2.pl
index eceb0dc533..2bd9173d42 100644
--- a/challenge-148/paulo-custodio/perl/ch-2.pl
+++ b/challenge-148/paulo-custodio/perl/ch-2.pl
@@ -2,7 +2,7 @@
 
 # Challenge 148
 #
-# TASK #2 › Cardano Triplets
+# TASK #2 > Cardano Triplets
 # Submitted by: Mohammad S Anwar
 # Write a script to generate first 5 Cardano Triplets.
 #
@@ -15,27 +15,47 @@
 # (2,1,5) is the first Cardano Triplets.
 
 use Modern::Perl;
+use List::Util 'sum';
 
-my $limit = 100;
 my @triplets = cardano_triplets(5);
-for (0..4) {
-    say "(", join(",", @{$triplets[$_]}), ")";
+for (@triplets) {
+    say "(", join(",", @$_), ")";
 }
 
-
 sub cardano_triplets {
-    my($n) = @_;
+    my($num) = @_;
 
-    my @found;
-    for my $a (1..$limit) {
-        for my $b (1..$limit) {
-            for my $c (1..$limit) {
-                if (8*($a**3)+15*($a**2)+6*$a-27*($b**2)*$c==1) {
-                    push @found, [$a, $b, $c];
-                }
+    my @triplets;
+    my $K = 0;
+    while (@triplets < $num*2) {        # we are not sure in which order they are generated
+        my $A = 2+3*$K;
+        my $T = ($K+1)**2 * (8*$K+5);
+        my @divs = divisors($T);
+        for my $div (@divs) {
+            if (int(sqrt($div)) == sqrt($div)) {
+                my $B = sqrt($div);
+                my $C = $T / $B**2;
+                push @triplets, [$A, $B, $C];
             }
         }
+        @triplets = sort {sum(@$a) <=> sum(@$b)} @triplets;
+
+        $K++;
     }
 
-    return @found;
+    return @triplets[0..$num-1];
+}
+
+sub divisors {
+    my($n) = @_;
+    my @divs1;
+    my @divs2;
+    for my $k (1 .. $n) {
+        last if @divs2 && $k >= $divs2[0];
+        if ($n % $k == 0) {
+            push @divs1, $k;
+            unshift @divs2, $n/$k;
+        }
+    }
+    return (@divs1, @divs2);
 }
diff --git a/challenge-148/paulo-custodio/python/ch-1.py b/challenge-148/paulo-custodio/python/ch-1.py
new file mode 100644
index 0000000000..9417ec6343
--- /dev/null
+++ b/challenge-148/paulo-custodio/python/ch-1.py
@@ -0,0 +1,26 @@
+#!/usr/bin/env python3
+
+# Challenge 148
+#
+# TASK #1 > Eban Numbers
+# Submitted by: Mohammad S Anwar
+# Write a script to generate all Eban Numbers <= 100.
+#
+# An Eban number is a number that has no letter 'e' in it when the number
+# is spelled in English (American or British).
+#
+# Example
+# 2, 4, 6, 30, 32 are the first 5 Eban numbers.
+
+from num2words import num2words
+
+def is_eban(n):
+    en = num2words(n)
+    return 'e' not in en
+
+out = []
+for n in range(1, 101):
+    if is_eban(n):
+        out.append(n)
+
+print(", ".join(map(str, out)))
diff --git a/challenge-148/paulo-custodio/python/ch-2.py b/challenge-148/paulo-custodio/python/ch-2.py
new file mode 100644
index 0000000000..73114e1555
--- /dev/null
+++ b/challenge-148/paulo-custodio/python/ch-2.py
@@ -0,0 +1,50 @@
+#!/usr/bin/env python3
+
+# Challenge 148
+#
+# TASK #2 > Cardano Triplets
+# Submitted by: Mohammad S Anwar
+# Write a script to generate first 5 Cardano Triplets.
+#
+# A triplet of positive integers (a,b,c) is called a Cardano Triplet if it
+# satisfies the below condition.
+#
+# Cardano Triplets
+#
+# Example
+# (2,1,5) is the first Cardano Triplets.
+
+from math import isqrt
+from itertools import chain
+
+def cardano_triplets(num):
+    triplets = []
+    K = 0
+    while len(triplets) < num * 2:  # we are not sure in which order they are generated
+        A = 2 + 3 * K
+        T = (K + 1) ** 2 * (8 * K + 5)
+        divs = divisors(T)
+        for div in divs:
+            if isqrt(div) ** 2 == div:
+                B = isqrt(div)
+                C = T // (B ** 2)
+                triplets.append((A, B, C))
+        triplets.sort(key=lambda x: sum(x))
+        K += 1
+
+    return triplets[:num]
+
+def divisors(n):
+    divs1 = []
+    divs2 = []
+    for k in range(1, n + 1):
+        if divs2 and k >= divs2[0]:
+            break
+        if n % k == 0:
+            divs1.append(k)
+            divs2.insert(0, n // k)
+    return list(chain(divs1, divs2))
+
+triplets = cardano_triplets(5)
+for triplet in triplets:
+    print(f"({','.join(map(str, triplet))})")
diff --git a/challenge-148/paulo-custodio/t/test-2.yaml b/challenge-148/paulo-custodio/t/test-2.yaml
index eb8432b926..c2b0ba83bf 100644
--- a/challenge-148/paulo-custodio/t/test-2.yaml
+++ b/challenge-148/paulo-custodio/t/test-2.yaml
@@ -4,7 +4,7 @@
   input:
   output:   |
             |(2,1,5)
-            |(5,1,52)
             |(5,2,13)
             |(8,3,21)
             |(11,4,29)
+            |(14,5,37)