Merge pull request hacktoberfest17#732 from raaloottan/raalootan

shell factorial

Author: t2013anurag

factorial/shell/factorial.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+fact=1
+#taking input from user
+echo -e "Please enter a finite possitive number"
+read n
+#if enter value less than 0
+if [ $n -le 0 ] ; then
+echo "invalid number"
+exit
+fi
+#factorial logic
+if [ $n -gt 0 ] ; then
+for((i=$n;i>=1;i--))
+do
+fact=`expr $fact \* $i`
+done
+fi
+echo "The factorial of $n is $fact"