1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143

// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

//! A Big integer (signed version: `BigInt`, unsigned version: `BigUint`).
//!
//! A `BigUint` is represented as a vector of `BigDigit`s.
//! A `BigInt` is a combination of `BigUint` and `Sign`.
//!
//! Common numerical operations are overloaded, so we can treat them
//! the same way we treat other numbers.
//!
//! ## Example
//!
//! ```rust
//! extern crate num_bigint;
//! extern crate num_traits;
//!
//! # fn main() {
//! use num_bigint::BigUint;
//! use num_traits::{Zero, One};
//! use std::mem::replace;
//!
//! // Calculate large fibonacci numbers.
//! fn fib(n: usize) -> BigUint {
//!     let mut f0: BigUint = Zero::zero();
//!     let mut f1: BigUint = One::one();
//!     for _ in 0..n {
//!         let f2 = f0 + &f1;
//!         // This is a low cost way of swapping f0 with f1 and f1 with f2.
//!         f0 = replace(&mut f1, f2);
//!     }
//!     f0
//! }
//!
//! // This is a very large number.
//! println!("fib(1000) = {}", fib(1000));
//! # }
//! ```
//!
//! It's easy to generate large random numbers:
//!
//! ```rust
//! extern crate rand;
//! extern crate num_bigint as bigint;
//!
//! # #[cfg(feature = "rand")]
//! # fn main() {
//! use bigint::{ToBigInt, RandBigInt};
//!
//! let mut rng = rand::thread_rng();
//! let a = rng.gen_bigint(1000);
//!
//! let low = -10000.to_bigint().unwrap();
//! let high = 10000.to_bigint().unwrap();
//! let b = rng.gen_bigint_range(&low, &high);
//!
//! // Probably an even larger number.
//! println!("{}", a * b);
//! # }
//!
//! # #[cfg(not(feature = "rand"))]
//! # fn main() {
//! # }
//! ```
#![doc(html_logo_url = "https://rust-num.github.io/num/rust-logo-128x128-blk-v2.png",
       html_favicon_url = "https://rust-num.github.io/num/favicon.ico",
       html_root_url = "https://rust-num.github.io/num/",
       html_playground_url = "http://play.integer32.com/")]

#[cfg(any(feature = "rand", test))]
extern crate rand;
#[cfg(feature = "rustc-serialize")]
extern crate rustc_serialize;
#[cfg(feature = "serde")]
extern crate serde;

extern crate num_integer as integer;
extern crate num_traits as traits;

use std::error::Error;
use std::num::ParseIntError;
use std::fmt;

#[derive(Debug, PartialEq)]
pub enum ParseBigIntError {
    ParseInt(ParseIntError),
    Other,
}

impl fmt::Display for ParseBigIntError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match self {
            &ParseBigIntError::ParseInt(ref e) => e.fmt(f),
            &ParseBigIntError::Other => "failed to parse provided string".fmt(f),
        }
    }
}

impl Error for ParseBigIntError {
    fn description(&self) -> &str {
        "failed to parse bigint/biguint"
    }
}

impl From<ParseIntError> for ParseBigIntError {
    fn from(err: ParseIntError) -> ParseBigIntError {
        ParseBigIntError::ParseInt(err)
    }
}

#[cfg(test)]
use std::hash;

#[cfg(test)]
fn hash<T: hash::Hash>(x: &T) -> u64 {
    use std::hash::Hasher;
    let mut hasher = hash::SipHasher::new();
    x.hash(&mut hasher);
    hasher.finish()
}

#[macro_use]
mod macros;

mod biguint;
mod bigint;

pub use biguint::BigUint;
pub use biguint::ToBigUint;
pub use biguint::big_digit;
pub use biguint::big_digit::{BigDigit, DoubleBigDigit, ZERO_BIG_DIGIT};

pub use bigint::Sign;
pub use bigint::BigInt;
pub use bigint::ToBigInt;
pub use bigint::RandBigInt;