Unix programs on simple logics

Unix program for amstrong number

The command given below is suitable for the computing in our saranathan college lab

echo "Enter the number"
read n
t=$n
s=0
b=0
c=10
while [ $n -gt $b ]
do
r=`expr $n % $c`
i=`expr $r \* $r \* $r`
s=`expr $s + $i`
n=`expr $n / $c`
done
echo $s
if [ $s -eq $t ]
then
echo "Amstrong number"
else
echo "Not an Armstrong number"
fi

---

Unix program for fibionacci series

The command given below is suitable for the computing in our saranathan college lab

echo "Enter the number"
read n
i=1
a=-1
fib=0
b=1
echo "Fibonacci series is"
while [ $i -lt $n ]
do
fib=`expr $a + $b`
a=$b
b=$fib
echo $fib
i=`expr $i + 1`
done

---

Unix program to check wheather the given number is prime or not

The command given below is suitable for the computing in our saranathan college lab

echo -n "Enter a number: "
read num
i=2

while [ $i -lt $num ]
do
if [ `expr $num % $i` -eq 0 ]
then
echo "$num is not a prime number"
echo "Since it is divisible by $i"
exit
fi
i=`expr $i + 1`
done

echo "$num is a prime number "