Shell Programming and Scripting

nawk '
  # a set of actions to be taken for every record/line
  {
   # initialize the "sum" to zero for current record/line
   sum=0
  
   # iterate through the fields starting at (i=2) till the maximum number of field (NF)
   # of the current record/line. For every iteration the the value of the currently 
   # iterated field ($i) to the sum (sum+=$i)
   for(i=2;i<=NF;i++) 
      sum+=$i

   # once the iteration loop is complete, print FIRST field and the "sum". 
   # The "," in the "print" statement get evaluated to the value of the OFS
   # OFS - OutputFieldSeparator
   print $1,sum

}' OFS=: myFile
# Assign ":" to OFS and pass the input file "myFile" to be be parsed by the script.

#!/usr/old/bin/sh
A2=0
A3=0
A4=0
TOTAL=0

cat Marks | awk '{print $1,$2,$3,$4}'|while read A1 A2 A3 A4
do
        if [ "${A2}""X" = "X" ]
        then
                A2=0
        fi
        if [ "${A3}""X" = "X" ]
        then
                A3=0
        fi
        if [ "${A4}""X" = "X" ]
        then
                A4=0
        fi
        #
        TOTAL=0
        TOTAL=`expr ${TOTAL} + ${A2}`
        TOTAL=`expr ${TOTAL} + ${A3}`
        TOTAL=`expr ${TOTAL} + ${A4}`
        echo "${A1}:${TOTAL}"
done[/CODE

#!/usr/old/bin/sh
A2=0
A3=0
A4=0
TOTAL=0

cat Marks |while read A1 A2 A3 A4
do
        if [ "${A2}""X" = "X" ]
        then
                A2=0
        fi
        if [ "${A3}""X" = "X" ]
        then
                A3=0
        fi
        if [ "${A4}""X" = "X" ]
        then
                A4=0
        fi
        #
        TOTAL=0
        TOTAL=`expr ${TOTAL} + ${A2}`
        TOTAL=`expr ${TOTAL} + ${A3}`
        TOTAL=`expr ${TOTAL} + ${A4}`
        echo "${A1}:${TOTAL}"
done

while read line;do
 set $line
 name=$1
 sum=0
 shift
 while [ $# -gt 0 ];do
        sum=$(($sum+$1))
        shift
 done
 echo $name" "$sum
done < a.txt