Update arithmetic.sh (#26)

* Update arithmetic.sh

* Update arithmetic.sh

* Update arithmetic.sh

operators/arithmetic.sh

@@ -1,10 +1,67 @@
 #!/bin/bash
 # ------------------------------------------------------------------------------------
-# Tutorial: brief description of tutorial content
+# Tutorial: Arithmatic operators. 
+            #Using expr : Here the expr command is used to evaluates the given expressions and display its corresponding output. The `expr` is similar to 'let,' but it does 
+            #not save the result to a variable. It directly prints the result.
+            #Syntax : $expr expression
+            #Using let : Let is a built-in command of Bash that allows us to perform arithmetic operations.
+            #Syntax : let <arithmetic expression>
+            #Using Double Parentheses : This is the easiest mechanism to perform basic arithmetic operations in the Bash shell. A leading $ may or may not be used.
 # ------------------------------------------------------------------------------------
 
-# Code here explaining concept with comments to guide
+# Take user Input
+echo "Enter first number : "
+read -r n1 
+echo "Enter second number : "
+read -r n2 
+
+#Addition using let
+#let "add = $(( n1 + n2 ))" 
+#echo "Sum= $add"  
+
+#Addition using double parentheses
+add=$((n1 + n2))              
+echo "Sum: $add"  
+
+#Subtraction using expr
+#dif=$(expr "$n1" - "$n2")              
+#echo "Diffference: $dif" 
+
+#Subtraction using double parentheses
+dif=$((n1 - n2))              
+echo "Difference: $dif" 
+
+#Multiplication using expr
+#mult=$(expr "$n1" \* "$n2") #:The multiplication operator * must be escaped when used in an arithmetic expression with expr. Escape it like \*
+#echo "Product: $mult" 
+
+#Multiplication using double parentheses
+mult=$((n1 * n2)) 
+echo "Product: $mult" 
+
+#Division using double parentheses
+div=$((n1/n2))   
+echo "Quotient: $div" 
+
+#Modulus using double parentheses
+((mod=n1 % n2))  
+echo "Remainder: $mod"    
+
+#Exponentiation using double parentheses
+echo "Exponentiation: $(( n1 ** n2 ))"  
+
+#Assigning a and b value n1 and n2
+a=$n1
+b=$n2
+
+#Increment 
+echo "Increment of n1: $((++n1))"   
+echo "Increment of n2: $((++n2))"   
+
+#Decrement
+echo "Decrement of n1: $((--a))"   
+echo "Decrement of n2: $((--b))"   
 
 # ------------------------------------------------------------------------------------
-# Challenge: list challenges to be completed here. minimum of one challenge per tutorial
+# Challenge: Make a simple calculator with all the arithmetic operators.
 # ------------------------------------------------------------------------------------