priority

#!/bin/bash
echo "Enter number of process"
read n

echo "Enter process , AT , BT , Priority"
for (( i = 1; i <= n; i++ ))
do
    read p[$i]
    read at[$i]
    read bt[$i]
    read pr[$i]
done

for(( i = 1; i <= n-1 ; i++))
do
    for(( j = 1; j <= n-i; j++))
    do
        if [ ${at[$j]} -gt ${at[$j+1]} ]
        then
            temp=${at[$j]}
            at[$j]=${at[$j+1]}
            at[$j+1]=$temp

            temp=${bt[$j]}
            bt[$j]=${bt[$j+1]}
            bt[$j+1]=$temp

            temp=${pr[$j]}
            pr[$j]=${pr[$j+1]}
            pr[$j+1]=$temp


            temp=${p[$j]}
            p[$j]=${p[$j+1]}
            p[$j+1]=$temp
        fi
    done
done

ct=`expr ${at[1]} + ${bt[1]} `
tat=`expr $ct - ${at[1]} `
wt[1]=`expr $tat - ${bt[1]} `

for(( i=2; i<=n-1; i++ ))
do
    for(( j=2; j<=n-1; j++ ))
    do
        if [ ${pr[$j]} -gt ${pr[$j+1]} ]
        then

            temp=${at[$j]}
            at[$j]=${at[$j+1]}
            at[$j+1]=$temp

            temp=${bt[$j]}
            bt[$j]=${bt[$j+1]}
            bt[$j+1]=$temp

            temp=${p[$j]}
            p[$j]=${p[$j+1]}
            p[$j+1]=$temp

            temp=${pr[$j]}
            pr[$j]=${pr[$j+1]}
            pr[$j+1]=$temp
        fi
    done
done

for(( i=2; i<=n; i++ ))
do
    ct=`expr $ct + ${bt[$i]} `
    tat=`expr $ct - ${at[$i]} `
    wt[i]=`expr $tat - ${bt[$i]} `
done

twt=0

for(( i=1; i<=n; i++))
do
    twt=`expr $twt + ${wt[i]} `
done

echo $twt

awt=`expr $twt / $n `

echo $awt