ch-2 of wk 122

2 files changed, 84 insertions, 0 deletions

diff --git a/challenge-122/cheok-yin-fung/perl/ch-2.pl b/challenge-122/cheok-yin-fung/perl/ch-2.pl
new file mode 100644
index 0000000000..297d383e62
--- /dev/null
+++ b/challenge-122/cheok-yin-fung/perl/ch-2.pl
@@ -0,0 +1,84 @@
+#!/usr/bin/perl
+# The Weekly Challenge 122
+# Task 2 Basketball Points
+use strict;
+use warnings;
+use v5.10.0;
+use Algorithm::Combinatorics qw /combinations/;
+
+my $S = $ARGV[0] || 5;
+my @ans;
+
+if ($S == 1) {
+    @ans = ("1");
+}
+elsif ($S == 2) {
+    @ans = ("11","2");
+}
+else {
+    push @ans, reverse oneortwo_str($S)->@*;
+    for my $k (1..int $S/3) {
+        my @ans_three333;
+        my $iter = combinations([0..$S-1-2*$k], $k);
+        while (my $c = $iter->next) {
+            my $str_t = "*" x $S;
+            my $len = $S-2*$k;
+            substr($str_t, $c->[0], 3) = "3";
+            if ($k > 1) {
+              for my $t (reverse 1..$k-1) {
+                  substr($str_t, 2*($t-1)+$c->[$t], 3) = "3";
+              }
+            }            
+            push @ans_three333, $str_t;
+        }
+        push @ans, @{expand($_)} for (reverse @ans_three333);
+    }
+}
+
+say "Number of ways: " , scalar @ans;
+say "";
+say join "\n", @ans;
+
+sub expand {
+    my $str = $_[0];
+    my @expand_arr;
+    my $next_3;
+    if ($str =~ /\*/) {
+        my $pos = index($str,"*");
+        my $next_3 = index($str, "3", $pos+1);
+        my $len_of_stars =
+                           $next_3 == -1 ? 
+                           (length $str) - $pos :
+                           $next_3-$pos;
+    
+        for my $onetwo (oneortwo_str($len_of_stars)->@*) {
+            my $temp_str = $str;
+            substr($temp_str, $pos, $len_of_stars) = $onetwo;
+            push @expand_arr, @{expand($temp_str)};
+        }
+    }
+    else {
+        push @expand_arr, $str;
+    }
+    return [@expand_arr];
+}
+
+
+# codes from challenge 112
+sub oneortwo_str {
+    my $n = $_[0];
+    my @one_or_two;
+    return [] if $n == 0;
+    return ["1"] if $n == 1;
+    for my $i ($n%2+$n/2 .. $n-1) {
+        my $iter = combinations([0..$i-1] , ($n-$i) );
+        my $str = "1" x $i;
+        while (my $c = $iter->next) {
+            my $str_clone = $str;
+            substr($str_clone, $_, 1) = "2" for (@{$c});
+            push @one_or_two, $str_clone;
+        }
+    }
+    push @one_or_two , "1" x $n;
+    return [@one_or_two];
+}
diff --git a/logo-design/cheok-yin-fung/README b/logo-design/cheok-yin-fung/README.md
index 892ba2bcd1..892ba2bcd1 100644
--- a/logo-design/cheok-yin-fung/README
+++ b/logo-design/cheok-yin-fung/README.md