This is the draft project where you can start practicing TDD and pair-programming while building a calculator application.

The application can execute an arithmetic expression given as a single command line argument.

You can do it your own way or try to achieve the following tasks.

• When it receives no arguments returns a usage help string

• When it receives multiple arguments returns a usage help string

• When it receives an integer returns it as a result

• Can execute an addition expression between two integers

• Can execute an addition expression between any number of integers

• Can execute an addition expression between any number of floating-point numbers

• Can execute an subtraction expression between two integers

• Can execute an subtraction expression between any number of integers

• Can execute an subtraction expression between any number of floating-point numbers

• Can execute a mixed addition and subtraction expression

• Can execute a multiplication expression between two integers

• Can execute a multiplication expression between any number of integers

• Can execute a multiplication expression between any number of floating-point numbers

• Can execute a mixed addition, subtraction and multiplication expression

You can continue the exercise adding more functions. E.g.

• division
• brackets
• ...