From 93e58e2c9e1b29de4a0e6f2562ea67038f5ca810 Mon Sep 17 00:00:00 2001
From: Fung Cheok Yin <61836418+E7-87-83@users.noreply.github.com>
Date: Sat, 13 Jun 2020 19:42:54 +0800
Subject: Add files via upload

---
 ch-2.pl | 174 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 174 insertions(+)
 create mode 100644 ch-2.pl

(limited to 'ch-2.pl')

diff --git a/ch-2.pl b/ch-2.pl
new file mode 100644
index 0000000000..2c04455b3a
--- /dev/null
+++ b/ch-2.pl
@@ -0,0 +1,174 @@
+#!/usr/bin/perl
+use strict;
+use Math::Combinatorics;
+use List::Util qw{sum};
+
+
+#ref Challenge-051 task-1 3 Sum
+#brute force
+
+#my $S = "perlweeklychallenge";
+#my @W = ("weekly", "challenge", "perl");
+my $S;
+my @W;
+
+if ($ARGV[0] eq undef) {
+    $S = "thequickbrownfoxjumpsoverthelazydogwooyousee";
+    @W = split / /, "theq uickb rownf ox jumps over the lazy dog";
+} else {
+    $S = shift @ARGV;
+    @W = @ARGV;
+}
+
+my $target = length $S;
+
+my $noofsoln = 0;
+
+for my $r (1..$#W+1) {
+    my $subject = Math::Combinatorics->new( count => $r , data => [@W] );
+    while (my @tsum = $subject->next_combination) {
+        if ($target == sum map {length $_} @tsum) {
+            my $psubject = Math::Combinatorics->new( count => $r, data => [@tsum]);
+            while (my @ptsum = $psubject->next_permutation) {
+                if ( $S eq (join "", @ptsum)) {
+                    print "\"";
+                    print join "\",\"", @ptsum;
+                    print "\"\n";
+                    $noofsoln++;
+                }
+            }
+        }
+    }
+}
+
+print "0\n" if $noofsoln == 0;
+
+
+=pod
+Input
+
+my $S = "thequickbrownfoxjumpsoverthelazydog";
+my @W = split / /, "the quick brown fox jumps over the lazy dog";
+push @W, "theq", "uickb", "rownf", "ox";
+
+$ time perl ch-2.pl
+"the","quick","brown","fox","jumps","over","the","lazy","dog"
+"the","quick","brown","fox","jumps","over","the","lazy","dog"
+"theq","uickb","rownf","ox","jumps","over","the","lazy","dog"
+"theq","uickb","rownf","ox","jumps","over","the","lazy","dog"
+
+real	5m7.153s
+user	5m6.496s
+sys	0m0.076s
+
+
+---
+on performance
+
+$S = "thequickbrownfoxjumpsoverthelazydog";
+@W = split / /, "theq uickb rownf ox jumps over the lazy dog";
+$ time perl ch-2.pl
+"theq","uickb","rownf","ox","jumps","over","the","lazy","dog"
+
+real	0m2.729s
+user	0m2.727s
+sys	0m0.001s
+
+
+$S = "thequickbrownfoxjumpsoverthelazydogwoo";
+@W = split / /, "theq uickb rownf ox jumps over the lazy dog woo";
+$ time perl ch-2.pl
+"theq","uickb","rownf","ox","jumps","over","the","lazy","dog","woo"
+
+real	0m22.516s
+user	0m22.499s
+sys	0m0.009s
+
+
+
+$S = "thequickbrownfoxjumpsoverthelazydogwooyousee";
+@W = split / /, "theq uickb rownf ox jumps over the lazy dog woo you see";
+$ time perl ch-2.pl
+"theq","uickb","rownf","ox","jumps","over","the","lazy","dog","woo","you","see"
+
+real	46m17.928s
+user	46m14.609s
+sys	0m0.448s
+
+
+
+
+see the performance on single alphabet:
+
+$ time perl ch-2.pl abc a b c
+"a","b","c"
+
+real	0m0.019s
+user	0m0.015s
+sys	0m0.004s
+
+
+$ time perl ch-2.pl abcd a b c d
+"a","b","c","d"
+
+real	0m0.024s
+user	0m0.024s
+sys	0m0.000s
+
+
+$ time perl ch-2.pl abcde a b c d e
+"a","b","c","d","e"
+
+real	0m0.021s
+user	0m0.018s
+sys	0m0.004s
+
+
+$ time perl ch-2.pl abcdef a b c d e f
+"a","b","c","d","e","f"
+
+real	0m0.027s
+user	0m0.027s
+sys	0m0.000s
+
+
+$ time perl ch-2.pl abcdefg a b c d e f g
+"a","b","c","d","e","f","g"
+
+real	0m0.048s
+user	0m0.048s
+sys	0m0.000s
+
+
+$ time perl ch-2.pl abcdefgh a b c d e f g h
+"a","b","c","d","e","f","g","h"
+
+real	0m0.202s
+user	0m0.197s
+sys	0m0.004s
+
+
+$ time perl ch-2.pl abcdefghi a b c d e f g h i
+"a","b","c","d","e","f","g","h","i"
+
+real	0m1.692s
+user	0m1.691s
+sys	0m0.000s
+
+
+$ time perl ch-2.pl abcdefghij a b c d e f g h i j
+"a","b","c","d","e","f","g","h","i","j"
+
+real	0m18.022s
+user	0m17.954s
+sys	0m0.028s
+
+
+$ time perl ch-2.pl abcdefghijk a b c d e f g h i j k
+"a","b","c","d","e","f","g","h","i","j","k"
+
+real	3m21.870s
+user	3m21.691s
+sys	0m0.004s
+
+=cut
-- 
cgit