Simple calculator

Demonstrates a simple calculator.

As a mathematician
So I can add numbers
I want to add two numbers on my calc

As a mathematician
So I can subtract
I want to subtract two numbers on my calc

As mathematician
So I can enjoy the output of the calculator
I want a pretty output

Name		Name	Last commit message	Last commit date
Latest commit History 4 Commits
lib		lib
spec		spec
.rspec		.rspec
README.md		README.md

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