Merge pull request #3542 from drbaggy/master

Save a few bytes by trimming the subroutine name, and using pop rather than shift! and removing extraneous ;

1 files changed, 46 insertions, 30 deletions

diff --git a/challenge-100/james-smith/perl/ch-1.pl b/challenge-100/james-smith/perl/ch-1.pl
index e241822661..57352d1f30 100644
--- a/challenge-100/james-smith/perl/ch-1.pl
+++ b/challenge-100/james-smith/perl/ch-1.pl
@@ -6,6 +6,18 @@ use warnings;
 use feature qw(say);
 use Test::More;
 
+is( ft( '05:15pm' ), '17:15' );
+is( ft( '05:15 pm' ), '17:15' );
+is( ft( '17:15' ), '05:15pm' );
+is( ft( '05:15am' ), '05:15' );
+is( ft( '05:15 am' ), '05:15' );
+is( ft( '05:15' ), '05:15am' );
+is( ft( '00:00' ), '12:00am' );
+is( ft( '12:00' ), '12:00pm' );
+is( ft( '24:00' ), '12:00pm' );
+is( ft( '12:00 am' ), '00:00' );
+is( ft( '12:00 pm' ), '12:00' );
+
 is( fun_time( '05:15pm' ), '17:15' );
 is( fun_time( '05:15 pm' ), '17:15' );
 is( fun_time( '17:15' ), '05:15pm' );
@@ -18,52 +30,56 @@ is( fun_time( '24:00' ), '12:00pm' );
 is( fun_time( '12:00 am' ), '00:00' );
 is( fun_time( '12:00 pm' ), '12:00' );
 
-is( fun_time_readable( '05:15pm' ), '17:15' );
-is( fun_time_readable( '05:15 pm' ), '17:15' );
-is( fun_time_readable( '17:15' ), '05:15pm' );
-is( fun_time_readable( '05:15am' ), '05:15' );
-is( fun_time_readable( '05:15 am' ), '05:15' );
-is( fun_time_readable( '05:15' ), '05:15am' );
-is( fun_time_readable( '00:00' ), '12:00am' );
-is( fun_time_readable( '12:00' ), '12:00pm' );
-is( fun_time_readable( '24:00' ), '12:00pm' );
-is( fun_time_readable( '12:00 am' ), '00:00' );
-is( fun_time_readable( '12:00 pm' ), '12:00' );
-
 done_testing();
 
 ## 72 chars ############################################################
-## Just split so slightly more readable and fits on 72 char lines
 
-sub fun_time { $_[0]=~s{(\d+):(\d+)\s*(\wm|)}{sprintf'%02d:%02d%s',
-  ($1%12||(12*!$3))+12*('pm'eq$3),$2,$3?'':$1>11?'pm':'am'}re; }
+## Just split so slightly more readable and fits on 60 char lines
+## Not nasty hack - we pop rather than shift as it saves 2 bytes!
+## We assume that the minute portion will be two digits after the
+## ":" then we don't need to check it....
+
+## 110 bytes total - 102 inside the curly braces..
+
+sub ft{pop=~s/(.+)(:..)\s*(.m|)/sprintf'%02d%s%s',
+($1%12||(12*!$3))+12*('pm'eq$3),$2,$3?'':$1<12?'am':'pm'/re}
 
 ## This is more readable version with notes...
-sub fun_time_readable {
-  return $_[0] =~
-    s{
-        ## Split into 3 parts, $1 - hours, $2 - minutes & $3 - am/pm
-      (\d+) : (\d+) \s* ( \wm | )
+sub fun_time {
+  return pop =~
+    ## Note the nasty hack we pop rather than shift - that saves 2 bytes
+    ## in our golfdom....
+    s/
+        ## Split into 3 parts, $1 - hours, $2 - minutes & $3 - am-pm
+      (.+) (:..) \s* ( .m | )
         ## We assume all strings are valid - so we don't have to anchor
         ## at both ends or worry what the 12hr clock sufficies are
-        ## am/pm & \wm is shorter than [ap]m
+        ## am-pm and .m is shorter than [ap]m
+        ##
+        ## We assume that the time will always have a : followed
+        ## 2 digits...
         ##
-        ## Note if we right (\wm)? the 3rd capture variable $3 is
-        ## sometimes undefined - better is to use ([ap]m|) which
+        ## Note if we right (.m)? the 3rd capture variable $3 is
+        ## sometimes undefined - better is to use (.m|) which
         ## matches the same way but $3 is now an empty string not
         ## undefined when we have a 24 hour clock time
-    }
-    {
-      sprintf '%02d:%02d%s',
-        ( $1%12 || (12*!$3) ) + 12*('pm'eq$3),
+    /
+      sprintf '%02d%s%s',
+        ( $1 % 12 || ( 12 * ! $3 ) ) + 12 * ( 'pm' eq $3 ),
           ## Get hour modulo 12..
           ## From 24hr to 12hr clock we need to convert 00:?? to 12:??
           ## From 12hr to 24hr clock it is pm we then need to add 12...
+          ## Note we use the "yoda condition" for the equals
+          ##   'pm'eq$3
+          ## as this is a byte shorter than the more usual way of
+          ## writing inequalitys
+          ##   $3 eq'pm'
+          ## as we don't need a space between the $3 & the eq...
         $2,
           ## The minutes is the easy bit just copy..
-        $3 ? '' : $1>11 ? 'pm' : 'am'
+        $3 ? '' : $1 < 12 ? 'am' : 'pm'
           ## If we are converting from 12hr clock the third string is
-          ## empty - if not and the time is <12 we return am o/w  pm
-    }rex;
+          ## empty - if not and the time is <12 we return am otherwise pm
+    /rex;
 }