Fermat-FasterCoding 1.0.1

Example code for the Fermats-Little-Theorem modular inverse algorithm

Fermats Little Theorem

This repository contains an example of the Fermats Little Theorem algorithm for C++ and one for Python3.

C++

To run the example for C++ change into the c++ folder and run the following bash script in Linux.

mkdir build && \
cd build && \
cmake .. -G "Unix Makefiles" && \
make

The program should be build and you can see an executable called modinverse.

You can test it with ./modinverse arg1 arg2.

For example:

./modinverse 3 5
modular inverse of 3 mod 5 is 2

./modinverse 2 4
There is no modular inverse!

./modinverse 2  
Not enough input arguments!

Python3

You can run this example from source or install it with pip and include it in your project.

Source

Requirement

• virtualenv

To run this example from source, run the following bash script in Linux.

python3 -m virtualenv . && \
source ./bin/activate && \
pip3 install -r requirements.txt

This will generate a virual environment and install the requirement.

After that you can run the programm with

python3 Fermat/fermat.py arg1 arg2

For example:

python3 Fermat/fermat.py 2 5
The mod inverse of 2 mod 5 is 3

python3 Fermat/fermat.py 2 4
There is no modular inverse!

python3 Fermat/fermat.py 2  
Not enough input arguments!

Pip

To install this example with pip, simply run:

pip3 install Fermat-FasterCoding

Then you can use it as import like this:

import Fermat.fermat as fermat

inverse = fermat.modInverse(3, 5) # This will return 2