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// Copyright © 2026 Mikhail Hogrefe
//
// This file is part of Malachite.
//
// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
use cratePrimitiveInt;
// Twice the width of a `u64`, in bits (128). Shared by the double-limb square-residue mask
// (`is_square`) and the prime sieve.
pub const TWICE_U64_WIDTH: u64 = u64WIDTH << 1;
/// [`Factor`](traits::Factor), a trait for computing the prime factorization of a number.
/// [`IsPower`](traits::IsPower) and [`ExpressAsPower`](traits::ExpressAsPower), traits for testing
/// if a number is a perfect power and, if it is, expressing it as such.
///
/// # is_power
/// ```
/// use malachite_base::num::factorization::traits::IsPower;
///
/// assert!(0u8.is_power());
/// assert!(1u16.is_power());
/// assert!(36u32.is_power());
/// assert!(64u32.is_power());
/// assert!(100u64.is_power());
/// assert!(1728u64.is_power());
///
/// assert!(0u8.is_power());
/// assert!(1u16.is_power());
/// assert!(!2u64.is_power());
/// assert!(!3u64.is_power());
/// ```
///
/// # express_as_power
/// ```
/// use malachite_base::num::factorization::traits::ExpressAsPower;
///
/// assert_eq!(0u8.express_as_power().unwrap(), (0, 2));
/// assert_eq!(1u16.express_as_power().unwrap(), (1, 2));
/// assert_eq!(36u32.express_as_power().unwrap(), (6, 2));
/// assert_eq!(64u32.express_as_power().unwrap(), (2, 6));
/// assert_eq!(100u64.express_as_power().unwrap(), (10, 2));
/// assert_eq!(1728u64.express_as_power().unwrap(), (12, 3));
///
/// assert!(0u8.express_as_power().is_some());
/// assert!(1u16.express_as_power().is_some());
/// assert!(2u64.express_as_power().is_none());
/// assert!(3u64.express_as_power().is_none());
/// ```
/// [`IsPrime`](traits::IsPrime), a trait for testing a number for primality.
/// [`IsSquare`](traits::IsSquare), a trait for testing if a number if a perfect square.
///
/// # is_square
/// ```
/// use malachite_base::num::factorization::traits::IsSquare;
///
/// assert!(0u8.is_square());
/// assert!(1u16.is_square());
/// assert!(4u32.is_square());
/// assert!(256u64.is_square());
///
/// assert!(!2u8.is_square());
/// assert!(!5u16.is_square());
/// assert!(!8u32.is_square());
/// assert!(!128u64.is_square());
/// ```
/// An efficient prime sieve.
/// [`Primes`](traits::Primes), a trait for generating prime numbers.
///
/// # primes_less_than
/// ```
/// use itertools::Itertools;
/// use malachite_base::num::factorization::traits::Primes;
///
/// assert_eq!(u8::primes_less_than(&10).collect_vec(), &[2, 3, 5, 7]);
/// assert_eq!(u16::primes_less_than(&11).collect_vec(), &[2, 3, 5, 7]);
/// assert_eq!(
/// u32::primes_less_than(&100).collect_vec(),
/// &[
/// 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
/// 89, 97
/// ]
/// );
/// ```
///
/// # primes_less_than_or_equal_to
/// ```
/// use itertools::Itertools;
/// use malachite_base::num::factorization::traits::Primes;
///
/// assert_eq!(
/// u8::primes_less_than_or_equal_to(&10).collect_vec(),
/// &[2, 3, 5, 7]
/// );
/// assert_eq!(
/// u16::primes_less_than_or_equal_to(&11).collect_vec(),
/// &[2, 3, 5, 7, 11]
/// );
/// assert_eq!(
/// u32::primes_less_than_or_equal_to(&100).collect_vec(),
/// &[
/// 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
/// 89, 97
/// ]
/// );
/// ```
///
/// # primes
/// ```
/// use itertools::Itertools;
/// use malachite_base::num::factorization::traits::Primes;
///
/// assert_eq!(
/// u8::primes().collect_vec(),
/// &[
/// 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83,
/// 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179,
/// 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251
/// ]
/// );
/// ```
/// [`PrimitiveRootPrime`](traits::PrimitiveRootPrime), a trait for finding a primitive root modulo
/// a prime number.
///
/// # primitive_root_prime
/// ```
/// use malachite_base::num::factorization::traits::PrimitiveRootPrime;
///
/// assert_eq!(5u32.primitive_root_prime(), 2);
/// assert_eq!(191u32.primitive_root_prime(), 19);
/// assert_eq!(4294967291u32.primitive_root_prime(), 2);
/// ```
/// [`RemovePower`](traits::RemovePower) and [`RemovePowerAssign`](traits::RemovePowerAssign),
/// traits for dividing out the largest power of a factor.
///
/// # remove_power
/// ```
/// use malachite_base::num::factorization::traits::RemovePower;
///
/// assert_eq!(12u32.remove_power(2), (3, 2));
/// // the factor need not be prime
/// assert_eq!(1000u32.remove_power(10), (1, 3));
/// // a factor that does not divide at all is removed zero times
/// assert_eq!(7u32.remove_power(3), (7, 0));
/// // zero is left alone
/// assert_eq!(0u32.remove_power(3), (0, 0));
///
/// // for signed types the quotient is the exact division by the signed power
/// assert_eq!((-12i32).remove_power(2), (-3, 2));
/// assert_eq!((-8i32).remove_power(-2), (1, 3));
/// ```
///
/// # remove_power_assign
/// ```
/// use malachite_base::num::factorization::traits::RemovePowerAssign;
///
/// let mut x = 12u32;
/// assert_eq!(x.remove_power_assign(2), 2);
/// assert_eq!(x, 3);
///
/// let mut x = -8i32;
/// assert_eq!(x.remove_power_assign(-2), 3);
/// assert_eq!(x, 1);
/// ```
/// Various traits for generating primes, primality testing, and factorization.