# Big_Unsigned_Ints

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## Description

**Big_Unsigned_Ints** is a crate for Rust that allows you to use large unsigned integers ranging from U256 through U2048. These are implemented using fixed-sized arrays and converts from u8 to u64 types. It also allows you to convert back from u64 to an array of u8s without using unsafe code.

The u8 -> u64 conversion uses mem::transmute with unsafe code to perform the process.

No functions should be used aside from the standard traits From and Into to convert between u8 and u64.

## How To Use

Write the following inside your cargo.toml file under dependencies:

`big_unsigned_ints = "0.1.6"`

Then, you can import it like so:

```rust
extern crate big_unsigned_ints;
```

Please view the tests folder for integration testing and how you can use the library itself.

## Standard Documentation On Usage

### Converting Array of Bytes To U256 Type

```rust
fn example_bytes (){
    // 32-fixed sized array of bytes
    let x = [243u8;32];

    // Conversion Occurs From Bytes of Array To The Type
    let y = big_unsigned_ints::U256::from(x);

    // Prints as Hexadecimal
    println!("{}",y)
}
```

### Converting Array of Bytes To U256 Type Back To An Array Of Bytes

```rust
fn bytes_to_big_int (){
    // Create an array of 32x 243u8, or 256bits
    let x = [243u8;32];

    // Convert From the Array of Bytes Into a U256 Type ([u64;4])
    let y = big_unsigned_ints::U256::from(x);

    // Convert Back Into An Array of Bytes Specifying the Type For Bytes
    let b: [u8;32] = y.into();
}
```

## Available Types

* U256 `[u64;4]` | `[u8;32]`

* U384 `[u64;6]` | `[u8;48]`

* U512 `[u64;8]` | `[u8;64]`

* U1024 `[u64;16]` | `[u8;128]`

* U2048 `[u64;32]` | `[u8;256]`

## License

* MIT License

* Apache 2.0