Q1
Write a basic command line calculator. Calculator will wait for user (with ‘>’ symbol) to enter an expression containing only one operator and two operands. Calculator will print the result of expression to the screen and will wait for another one till the user enters a command, called “quit” , to terminate the program. Calculation program must control type of operands and should make cast operations (integer to float) if necessary. Also user must be warned for operators which are not listed below with a warning message, “illegal operator”. An extra message, “illegal operand” should be given if necessary (an example is given below)

Operation and operator which must be supported by calculator are given below:

• Addition…………( + )
• Subtraction………( – )
• Multiplication…...( x )
• Division…………( / )
• Modulo………….( % )
• Power……………( ^ )

Note : You must read user input (operator and operands) as a string at once.

Example flow of program

[cihan@tweety ~]# ./calc
>10+15
25
>3x34
102
>0.3x5
1.5
>3.5%2
Illegal operand
>4*4
Illegal operator
>quit
[cihan@tweety ~]#