SHELL PROGRAM

ARMSTRONG NUMBER 

echo"Enter the number"

read n

t=$n

s=0

b=0

c=10

while[$n -st $b]

do 

r='expr $n%$c'

i='expr $r \*$r\*$r'

s='expr $s + $i'

n='expr $n / $c'

done

echo a$s

if[ $s -eq $t]

then 

echo"Armstrong number"

else "Not an Armstrong number"

fi

THE GIVEN NUMBER IS PRIME OR NOT

echo"Enter a number:"

read n

flag=0

for((i=2;i<=n/2;i++))

do

r='expr $n %$i'

if[ $r = 0]

then

flag=1

break

fi

done

if [ $flag = 0]

then

 echo"$n is a prime number"

else

echo"$n is not a prime number"

fi