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use malachite_base::num::arithmetic::traits::{Sign, UnsignedAbs};
use malachite_base::num::basic::traits::One;
use malachite_base::num::conversion::traits::ExactFrom;
use malachite_base::num::logic::traits::SignificantBits;
use malachite_nz::natural::Natural;
use std::cmp::Ordering;
use Rational;
fn partial_cmp_unsigned<T: Copy + One + Ord + Sign + SignificantBits>(
x: &Rational,
other: &T,
) -> Option<Ordering>
where
Natural: From<T> + PartialOrd<T>,
{
let self_sign = x.sign();
let other_sign = other.sign();
let sign_cmp = self_sign.cmp(&other_sign);
if sign_cmp != Ordering::Equal || self_sign == Ordering::Equal {
return Some(sign_cmp);
}
let self_cmp_one = x.numerator.cmp(&x.denominator);
let other_cmp_one = other.cmp(&T::ONE);
let one_cmp = self_cmp_one.cmp(&other_cmp_one);
if one_cmp != Ordering::Equal {
return Some(one_cmp);
}
let n_cmp = x.numerator.partial_cmp(other).unwrap();
let d_cmp = x.denominator.cmp(&Natural::ONE);
if n_cmp == Ordering::Equal && d_cmp == Ordering::Equal {
return Some(Ordering::Equal);
} else {
let nd_cmp = n_cmp.cmp(&d_cmp);
if nd_cmp != Ordering::Equal {
return Some(nd_cmp);
}
}
let log_cmp = x
.floor_log_base_2_of_abs()
.cmp(&i64::exact_from(other.significant_bits() - 1));
if log_cmp != Ordering::Equal {
return Some(if x.sign { log_cmp } else { log_cmp.reverse() });
}
Some(x.numerator.cmp(&(&x.denominator * Natural::from(*other))))
}
macro_rules! impl_unsigned {
($t: ident) => {
impl PartialOrd<$t> for Rational {
#[inline]
fn partial_cmp(&self, other: &$t) -> Option<Ordering> {
partial_cmp_unsigned(self, other)
}
}
impl PartialOrd<Rational> for $t {
#[inline]
fn partial_cmp(&self, other: &Rational) -> Option<Ordering> {
other.partial_cmp(self).map(Ordering::reverse)
}
}
};
}
apply_to_unsigneds!(impl_unsigned);
fn partial_cmp_signed<
U: Copy + One + Ord + SignificantBits,
S: Copy + Sign + SignificantBits + UnsignedAbs<Output = U>,
>(
x: &Rational,
other: &S,
) -> Option<Ordering>
where
Natural: From<U> + PartialOrd<U>,
{
let self_sign = x.sign();
let other_sign = other.sign();
let sign_cmp = self_sign.cmp(&other_sign);
if sign_cmp != Ordering::Equal || self_sign == Ordering::Equal {
return Some(sign_cmp);
}
let other_abs = other.unsigned_abs();
let self_cmp_one = x.numerator.cmp(&x.denominator);
let other_cmp_one = other_abs.cmp(&U::ONE);
let one_cmp = self_cmp_one.cmp(&other_cmp_one);
if one_cmp != Ordering::Equal {
return Some(if x.sign { one_cmp } else { one_cmp.reverse() });
}
let n_cmp = x.numerator.partial_cmp(&other_abs).unwrap();
let d_cmp = x.denominator.cmp(&Natural::ONE);
if n_cmp == Ordering::Equal && d_cmp == Ordering::Equal {
return Some(Ordering::Equal);
} else {
let nd_cmp = n_cmp.cmp(&d_cmp);
if nd_cmp != Ordering::Equal {
return Some(if x.sign { nd_cmp } else { nd_cmp.reverse() });
}
}
let log_cmp = x
.floor_log_base_2_of_abs()
.cmp(&i64::exact_from(other.significant_bits() - 1));
if log_cmp != Ordering::Equal {
return Some(if x.sign { log_cmp } else { log_cmp.reverse() });
}
let prod_cmp = x
.numerator
.cmp(&(&x.denominator * Natural::from(other_abs)));
Some(if x.sign { prod_cmp } else { prod_cmp.reverse() })
}
macro_rules! impl_signed {
($t: ident) => {
impl PartialOrd<$t> for Rational {
#[inline]
fn partial_cmp(&self, other: &$t) -> Option<Ordering> {
partial_cmp_signed(self, other)
}
}
impl PartialOrd<Rational> for $t {
#[inline]
fn partial_cmp(&self, other: &Rational) -> Option<Ordering> {
other.partial_cmp(self).map(Ordering::reverse)
}
}
};
}
apply_to_signeds!(impl_signed);