# CLI calculation tools
> `rfcalc` stands for "R4 Calculations". R4 is my self representaion =_=
## Installation
1. Intall Rust
2. Run `cargo install rfcalc`
## Usage
- `rfcalc factorial <NUM>`: Calculate the factorial of a number (max: 20)
- `rfcalc hw <NUM>`: Calculate the Hamming weight of a binary number
- `rfcalc c <N> <K>`: Calculate the combination of `N` choose `K`
### `rfcalc bytes <expression to calculate>`
Quickly devide bytes
> only support units of lower case now
E.g.
- `rfcalc bytes "4mb/4kb"` => `1024kb`
## Testing
```bash
cargo run -- <subcommand> <args>
```