Some bash shell script examples for beginners

 even odd

echo "Please enter a number"
read num
if [ `expr $num % 2`  == 0 ]
then
echo "$num is even"
else
echo "$num is odd"
fi

largest of three numbers

echo "please enter 3 numbers"
read num1
read num2
read num3

if test $num1 -gt $num2 -a $num1 -gt $num3
then
echo "$num1 is the greatest"
elif test $num2 -gt $num3
then
echo "$num2 is the greatest"
else
echo "$num3 is the greatest"
fi

calculate net salary

echo "enter basic salary"
read bs
hra=`echo $bs*10/100 | bc`
ta=`echo $bs*15/100 | bc`
da=`echo $bs*2/100 | bc`
pf=`echo $bs*10/100 | bc`
tax=`echo $bs*5/100 | bc`

netsal=`echo $bs+$hra+$ta+$da-$pf-$tax | bc`
echo "net salary is $netsal"

calculate conditional discount and tax

echo  "please enter the amount that you want to buy"
read amount
if test  $amount -lt 1000
then
tax=`echo $amount \* 2/100 | bc`
discount=`echo $amount \* 10/100 | bc`
else
tax=`echo $amount \* 5/100 | bc`
discount=`echo $amount \* 20/100 | bc`
fi

totalcost=`echo $amount - $tax + $discount | bc`
echo  "total cost is $totalcost"