Shell Programming and Scripting

#!/usr/bin/ksh
Month=`date|cut -c5-7`                         
Day=`date|cut -c9-10`                          
Year=`date|cut -c27-28`
Rom2Jul() { case $Month in Feb) Day=$(( $Day+31 ));;
                           Mar) Day=$(( $Day+59 ));;
                           Apr) Day=$(( $Day+90 ));;
                           May) Day=$(( $Day+120 ));;
                           Jun) Day=$(( $Day+151 ));;
                           Jul) Day=$(( $Day+181 ));;
                           Aug) Day=$(( $Day+212 ));;
                           Sep) Day=$(( $Day+243 ));;
                           Oct) Day=$(( $Day+273 ));;
                           Nov) Day=$(( $Day+304 ));;
                           Dec) Day=$(( $Day+334 ));; esac }
Rom2Jul

Current=$(( $Year*365+$Day-2 ))

PrevHostname=''
PrevBackup=0
while read input                               
do Month=${input:0:3}
   Day=${input:4:2}
   Hostname=${input:13:12}
   Rom2Jul
   if [[ ${input:9:1} = ':' ]] then Year=`date|cut -c27-28`; else Year=${input:10:2}; fi
   Backup=$(( $Year*365+$Day ))
   if [[ $PrevHostname = '' ]] then PrevHostname=$Hostname; PrevBackup=$Backup
      else if [[ $PrevHostname != $Hostname ]] then echo $PrevBackup $PrevHostname 
                                                    PrevHostname=$Hostname; PrevBackup=$Backup
              else if (( $Backup > $PrevBackup )) then PrevBackup=$Backup; fi; fi; fi; done 
echo $PrevBackup $PrevHostname

PrevHostname=''
PrevBackup=0
while read input                               
do Month=${input:0:3}
   Day=${input:4:2}
   Hostname=${input:13:12}