# Jubjub Curve
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This crate provides jubjub curve arithmetic and also supports fully `no_std` and [`parity-scale-codec`](https://github.com/paritytech/parity-scale-codec).

## Specification
The Jubjub curve is one of twisted edwards curve.

- Twisted Edwards Curve

$$
ax^2 + y^2 = 1 + dx^2y^2
$$

- Addition Law

$$
(x_3 = \frac{x_1y_1 + y_1x_1}{1 + dx_1x_1y_1y_1}, y_3 = \frac{y_1y_1 + ax_1x_1}{1 - dx_1x_1y_1y_1})
$$

## Test

```shell
$ cargo test
```