Merge pull request #8797 from simongreen-net/master

Simon's solution to challenge 236

6 files changed, 174 insertions, 2 deletions

diff --git a/challenge-236/sgreen/README.md b/challenge-236/sgreen/README.md
index f06edcdb27..c3256674bf 100644
--- a/challenge-236/sgreen/README.md
+++ b/challenge-236/sgreen/README.md
@@ -1,3 +1,3 @@
-# The Weekly Challenge 235
+# The Weekly Challenge 236
 
-Blog: [Adding and removing integers](https://dev.to/simongreennet/adding-and-removing-integers-3i4g)
+Blog: [Juicy loops](https://dev.to/simongreennet/juicy-loops-2di2)
diff --git a/challenge-236/sgreen/blog.txt b/challenge-236/sgreen/blog.txt
new file mode 100644
index 0000000000..d76a60ea88
--- /dev/null
+++ b/challenge-236/sgreen/blog.txt
@@ -0,0 +1 @@
+https://dev.to/simongreennet/juicy-loops-2di2
\ No newline at end of file
diff --git a/challenge-236/sgreen/perl/ch-1.pl b/challenge-236/sgreen/perl/ch-1.pl
new file mode 100755
index 0000000000..246983d32d
--- /dev/null
+++ b/challenge-236/sgreen/perl/ch-1.pl
@@ -0,0 +1,49 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use feature 'say';
+use experimental 'signatures';
+
+use List::Util 'min';
+
+sub main (@notes) {
+    # Store what is in the wallet, key is the dollar value, value is the
+    #  number of notes we have
+    my %wallet = ();
+
+  C: foreach my $customer_note (@notes) {
+        # Add the amount the person has given us
+        $wallet{$customer_note}++;
+
+        if ( $customer_note == 5 ) {
+            # No change required :)
+            next;
+        }
+
+        my $change = $customer_note - 5;
+
+        # We try the bigger notes first
+        foreach my $wallet_note ( sort { $b <=> $a } keys %wallet ) {
+            my $note_count =
+              min( $wallet{$wallet_note}, int( $change / $wallet_note ) );
+            if ( $note_count > 0 ) {
+                # Take the note from the wallet, and reduce the change still
+                #  to give
+                $wallet{$wallet_note} -= $note_count;
+                $change -= $wallet_note * $note_count;
+
+                if ( $change == 0 ) {
+                    next C;
+                }
+            }
+        }
+
+        say 'false';
+        return;
+    }
+
+    say 'true';
+}
+
+main(@ARGV);
\ No newline at end of file
diff --git a/challenge-236/sgreen/perl/ch-2.pl b/challenge-236/sgreen/perl/ch-2.pl
new file mode 100755
index 0000000000..db13ccb43d
--- /dev/null
+++ b/challenge-236/sgreen/perl/ch-2.pl
@@ -0,0 +1,42 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use feature 'say';
+use experimental 'signatures';
+
+use List::Util 'any';
+
+sub main (@ints) {
+    # Record all the loops we find
+    my $loops = 0;
+
+  F: foreach my $first ( 0 .. $#ints ) {
+        my @loop = ();
+        my $pos  = $first;
+
+        while ( $pos >= 0 and $pos <= $#ints and defined( $ints[$pos] ) ) {
+            push @loop, $pos;
+
+            # What is the next number
+            my $next_pos = $ints[$pos];
+
+            # Mark this position as used
+            $ints[$pos] = undef;
+
+            if ( any { $next_pos == $_ } @loop ) {
+                # We have a loop
+                ++$loops;
+                next F;
+            }
+
+            # Continue with the next position
+            $pos = $next_pos;
+        }
+    }
+
+    # Print the loops we found
+    say $loops;
+}
+
+main(@ARGV);
\ No newline at end of file
diff --git a/challenge-236/sgreen/python/ch-1.py b/challenge-236/sgreen/python/ch-1.py
new file mode 100755
index 0000000000..80ff481963
--- /dev/null
+++ b/challenge-236/sgreen/python/ch-1.py
@@ -0,0 +1,42 @@
+#!/usr/bin/env python3
+
+import sys
+
+
+def main(notes):
+    # Store what is in the wallet, key is the dollar value, value is the
+    #  number of notes we have
+    wallet = {}
+
+    for customer_note in notes:
+        # Add the amount the person has given us
+        wallet[customer_note] = wallet.get(customer_note, 0) + 1
+
+        if customer_note == 5:
+            # No change required :)
+            continue
+
+        change = customer_note - 5
+
+        # We try the bigger notes first
+        for wallet_note in sorted(wallet, reverse=True):
+            note_count = min(wallet[wallet_note], change // wallet_note)
+            if note_count > 0:
+                # Take the note from the wallet, and reduce the change still
+                #  to give
+                wallet[wallet_note] -= note_count
+                change -= wallet_note * note_count
+
+                if change == 0:
+                    break
+        else:
+            print('false')
+            return
+
+    print('true')
+
+
+if __name__ == '__main__':
+    # Convert input into integers
+    array = [int(n) for n in sys.argv[1:]]
+    main(array)
diff --git a/challenge-236/sgreen/python/ch-2.py b/challenge-236/sgreen/python/ch-2.py
new file mode 100755
index 0000000000..c0b0911a80
--- /dev/null
+++ b/challenge-236/sgreen/python/ch-2.py
@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+
+import sys
+
+
+def main(ints):
+    # Record all the loops we find
+    loops = 0
+
+    for first in range(len(ints)):
+        loop = []
+        pos = first
+
+        while pos >= 0 and pos < len(ints) and ints[pos] is not None:
+            loop.append(pos)
+
+            # What is the next number
+            next_pos = ints[pos]
+
+            # Mark this position as used
+            ints[pos] = None
+
+            if next_pos in loop:
+                # We have a loop
+                loops += 1
+                break
+
+            # Continue with the next position
+            pos = next_pos
+
+    # Print the loops we found
+    print(loops)
+
+
+if __name__ == '__main__':
+    # Convert input into integers
+    array = [int(n) for n in sys.argv[1:]]
+    main(array)