Calculator

An iOS command line calculator in Swift 4.2

Requirements

• Legal operators shall be *, /, +, - (multiply, divide, add, subtract)
• Operands and operators shall be separated by one or more spaces
• Mixed numbers will be represented by whole_numerator/denominator. e.g. "3_1/4"
• Improper fractions and whole numbers are also allowed as operands

Detailed instructions as stated in subject requirements:

You are to prepare a macOS command-line tool that will act as a simple calculator. The calculator will be run from the command line and will only work with integer numbers and the following arithmetic operators: + - x / `.

For example, if the program is compiled to Calculator, the following demonstrates how it will work

./Calculator 1/2 * 3_3/4 1_7/8

In the command line, the arguments are a repeated sequence in the form

number operator

and ending in a

number

Hitting the enter key will cause the program to evaluate the arguments and print the result. In this case 1_7/8.

The program must follow the usual rules of arithmetic which say:

1. The x and / operators must all be evaluated before the + and – operators.
2. Operators must be evaluated from left to right.

For example, using Rule 1

2_3/8 + 9/8

becomes

7/2

which results in

3_1/2

Running from the Command Line

• 1. Navigate to the project folder /.../Calculator/bin on the terminal
• 2. Run the command by typing in ./Calculator
• 3. Make sure to build first on Xcode, every time any modification made in code

Read default Arguments

• 1. In main.swit just change isTesting to true
• 2. Will active debug mode and read default arguments

For example, On terminal

./Calculator 3 + 5

become

8