--- /dev/null
+ /*!
+
+ A Big integer (signed version: BigInt, unsigned version: BigUint).
+
+ A BigUint is represented as an array of BigDigits.
+ A BigInt is a combination of BigUint and Sign.
+ */
+
+ use core::cmp::{Eq, Ord};
+ use core::num::{Num, Zero, One};
++use core::*;
+
+ /**
+ A BigDigit is a BigUint's composing element.
+
+ A BigDigit is half the size of machine word size.
+ */
+ #[cfg(target_arch = "x86")]
+ #[cfg(target_arch = "arm")]
+ pub type BigDigit = u16;
+
+ /**
+ A BigDigit is a BigUint's composing element.
+
+ A BigDigit is half the size of machine word size.
+ */
+ #[cfg(target_arch = "x86_64")]
+ pub type BigDigit = u32;
+
+ pub mod BigDigit {
+ #[cfg(target_arch = "x86")]
+ #[cfg(target_arch = "arm")]
+ pub const bits: uint = 16;
+
+ #[cfg(target_arch = "x86_64")]
+ pub const bits: uint = 32;
+
+ pub const base: uint = 1 << bits;
+ priv const hi_mask: uint = (-1 as uint) << bits;
+ priv const lo_mask: uint = (-1 as uint) >> bits;
+
+ priv pure fn get_hi(n: uint) -> BigDigit { (n >> bits) as BigDigit }
+ priv pure fn get_lo(n: uint) -> BigDigit { (n & lo_mask) as BigDigit }
+
+ /// Split one machine sized unsigned integer into two BigDigits.
+ pub pure fn from_uint(n: uint) -> (BigDigit, BigDigit) {
+ (get_hi(n), get_lo(n))
+ }
+
+ /// Join two BigDigits into one machine sized unsigned integer
+ pub pure fn to_uint(hi: BigDigit, lo: BigDigit) -> uint {
+ (lo as uint) | ((hi as uint) << bits)
+ }
+ }
+
+ /**
+ A big unsigned integer type.
+
+ A BigUint-typed value BigUint { data: @[a, b, c] } represents a number
+ (a + b * BigDigit::base + c * BigDigit::base^2).
+ */
+ pub struct BigUint {
+ priv data: ~[BigDigit]
+ }
+
+ impl BigUint : Eq {
+ pure fn eq(&self, other: &BigUint) -> bool { self.cmp(other) == 0 }
+ pure fn ne(&self, other: &BigUint) -> bool { self.cmp(other) != 0 }
+ }
+
+ impl BigUint : Ord {
+ pure fn lt(&self, other: &BigUint) -> bool { self.cmp(other) < 0 }
+ pure fn le(&self, other: &BigUint) -> bool { self.cmp(other) <= 0 }
+ pure fn ge(&self, other: &BigUint) -> bool { self.cmp(other) >= 0 }
+ pure fn gt(&self, other: &BigUint) -> bool { self.cmp(other) > 0 }
+ }
+
+ impl BigUint : ToStr {
+ pure fn to_str() -> ~str { self.to_str_radix(10) }
+ }
+
+ impl BigUint : from_str::FromStr {
+ static pure fn from_str(s: &str) -> Option<BigUint> {
+ BigUint::from_str_radix(s, 10)
+ }
+ }
+
+ impl BigUint : Shl<uint, BigUint> {
+ pure fn shl(&self, rhs: &uint) -> BigUint {
+ let n_unit = *rhs / BigDigit::bits;
+ let n_bits = *rhs % BigDigit::bits;
+ return self.shl_unit(n_unit).shl_bits(n_bits);
+ }
+ }
+
+ impl BigUint : Shr<uint, BigUint> {
+ pure fn shr(&self, rhs: &uint) -> BigUint {
+ let n_unit = *rhs / BigDigit::bits;
+ let n_bits = *rhs % BigDigit::bits;
+ return self.shr_unit(n_unit).shr_bits(n_bits);
+ }
+ }
+
+ impl BigUint : Zero {
+ static pure fn zero() -> BigUint { BigUint::new(~[]) }
+ }
+
+ impl BigUint : One {
+ static pub pure fn one() -> BigUint { BigUint::new(~[1]) }
+ }
+
+ impl BigUint : Num {
+ pure fn add(&self, other: &BigUint) -> BigUint {
+ let new_len = uint::max(self.data.len(), other.data.len());
+
+ let mut carry = 0;
+ let sum = do vec::from_fn(new_len) |i| {
+ let ai = if i < self.data.len() { self.data[i] } else { 0 };
+ let bi = if i < other.data.len() { other.data[i] } else { 0 };
+ let (hi, lo) = BigDigit::from_uint(
+ (ai as uint) + (bi as uint) + (carry as uint)
+ );
+ carry = hi;
+ lo
+ };
+ if carry == 0 { return BigUint::new(sum) };
+ return BigUint::new(sum + [carry]);
+ }
+
+ pure fn sub(&self, other: &BigUint) -> BigUint {
+ let new_len = uint::max(self.data.len(), other.data.len());
+
+ let mut borrow = 0;
+ let diff = do vec::from_fn(new_len) |i| {
+ let ai = if i < self.data.len() { self.data[i] } else { 0 };
+ let bi = if i < other.data.len() { other.data[i] } else { 0 };
+ let (hi, lo) = BigDigit::from_uint(
+ (BigDigit::base) +
+ (ai as uint) - (bi as uint) - (borrow as uint)
+ );
+ /*
+ hi * (base) + lo == 1*(base) + ai - bi - borrow
+ => ai - bi - borrow < 0 <=> hi == 0
+ */
+ borrow = if hi == 0 { 1 } else { 0 };
+ lo
+ };
+
+ assert borrow == 0; // <=> assert (self >= other);
+ return BigUint::new(diff);
+ }
+
+ pure fn mul(&self, other: &BigUint) -> BigUint {
+ if self.is_zero() || other.is_zero() { return Zero::zero(); }
+
+ let s_len = self.data.len(), o_len = other.data.len();
+ if s_len == 1 { return mul_digit(other, self.data[0]); }
+ if o_len == 1 { return mul_digit(self, other.data[0]); }
+
+ // Using Karatsuba multiplication
+ // (a1 * base + a0) * (b1 * base + b0)
+ // = a1*b1 * base^2 +
+ // (a1*b1 + a0*b0 - (a1-b0)*(b1-a0)) * base +
+ // a0*b0
+ let half_len = uint::max(s_len, o_len) / 2;
+ let (sHi, sLo) = cut_at(self, half_len);
+ let (oHi, oLo) = cut_at(other, half_len);
+
+ let ll = sLo * oLo;
+ let hh = sHi * oHi;
+ let mm = {
+ let (s1, n1) = sub_sign(sHi, sLo);
+ let (s2, n2) = sub_sign(oHi, oLo);
+ if s1 * s2 < 0 {
+ hh + ll + (n1 * n2)
+ } else if s1 * s2 > 0 {
+ hh + ll - (n1 * n2)
+ } else {
+ hh + ll
+ }
+ };
+
+ return ll + mm.shl_unit(half_len) + hh.shl_unit(half_len * 2);
+
+ pure fn mul_digit(a: &BigUint, n: BigDigit) -> BigUint {
+ if n == 0 { return Zero::zero(); }
+ if n == 1 { return copy *a; }
+
+ let mut carry = 0;
+ let prod = do vec::map(a.data) |ai| {
+ let (hi, lo) = BigDigit::from_uint(
+ (*ai as uint) * (n as uint) + (carry as uint)
+ );
+ carry = hi;
+ lo
+ };
+ if carry == 0 { return BigUint::new(prod) };
+ return BigUint::new(prod + [carry]);
+ }
+
+ pure fn cut_at(a: &BigUint, n: uint) -> (BigUint, BigUint) {
+ let mid = uint::min(a.data.len(), n);
+ return (BigUint::from_slice(vec::view(a.data, mid, a.data.len())),
+ BigUint::from_slice(vec::view(a.data, 0, mid)));
+ }
+
+ pure fn sub_sign(a: BigUint, b: BigUint) -> (int, BigUint) {
+ match a.cmp(&b) {
+ s if s < 0 => (s, b - a),
+ s if s > 0 => (s, a - b),
+ _ => (0, Zero::zero())
+ }
+ }
+ }
+
+ pure fn div(&self, other: &BigUint) -> BigUint {
+ let (d, _) = self.divmod(other);
+ return d;
+ }
+ pure fn modulo(&self, other: &BigUint) -> BigUint {
+ let (_, m) = self.divmod(other);
+ return m;
+ }
+
+ pure fn neg(&self) -> BigUint { fail }
+
+ pure fn to_int(&self) -> int {
+ uint::min(self.to_uint(), int::max_value as uint) as int
+ }
+
+ static pure fn from_int(n: int) -> BigUint {
+ if (n < 0) { Zero::zero() } else { BigUint::from_uint(n as uint) }
+ }
+ }
+
+ pub impl BigUint {
+ /// Creates and initializes an BigUint.
+ static pub pure fn new(v: ~[BigDigit]) -> BigUint {
+ // omit trailing zeros
+ let new_len = v.rposition(|n| *n != 0).map_default(0, |p| *p + 1);
+
+ if new_len == v.len() { return BigUint { data: v }; }
+ let mut v = v;
+ unsafe { v.truncate(new_len); }
+ return BigUint { data: v };
+ }
+
+ /// Creates and initializes an BigUint.
+ static pub pure fn from_uint(n: uint) -> BigUint {
+ match BigDigit::from_uint(n) {
+ (0, 0) => Zero::zero(),
+ (0, n0) => BigUint::new(~[n0]),
+ (n1, n0) => BigUint::new(~[n0, n1])
+ }
+ }
+
+ /// Creates and initializes an BigUint.
+ static pub pure fn from_slice(slice: &[BigDigit]) -> BigUint {
+ return BigUint::new(vec::from_slice(slice));
+ }
+
+ /// Creates and initializes an BigUint.
+ static pub pure fn from_str_radix(s: &str, radix: uint)
+ -> Option<BigUint> {
+ BigUint::parse_bytes(str::to_bytes(s), radix)
+ }
+
+ /// Creates and initializes an BigUint.
+ static pub pure fn parse_bytes(buf: &[u8], radix: uint)
+ -> Option<BigUint> {
+ let (base, unit_len) = get_radix_base(radix);
+ let base_num: BigUint = BigUint::from_uint(base);
+
+ let mut end = buf.len();
+ let mut n: BigUint = Zero::zero();
+ let mut power: BigUint = One::one();
+ loop {
+ let start = uint::max(end, unit_len) - unit_len;
+ match uint::parse_bytes(vec::view(buf, start, end), radix) {
+ Some(d) => n += BigUint::from_uint(d) * power,
+ None => return None
+ }
+ if end <= unit_len {
+ return Some(n);
+ }
+ end -= unit_len;
+ power *= base_num;
+ }
+ }
+
+ pure fn abs(&self) -> BigUint { copy *self }
+
+ /// Compare two BigUint value.
+ pure fn cmp(&self, other: &BigUint) -> int {
+ let s_len = self.data.len(), o_len = other.data.len();
+ if s_len < o_len { return -1; }
+ if s_len > o_len { return 1; }
+
+ for vec::rev_eachi(self.data) |i, elm| {
+ match (*elm, other.data[i]) {
+ (l, r) if l < r => return -1,
+ (l, r) if l > r => return 1,
+ _ => loop
+ };
+ }
+ return 0;
+ }
+
+ pure fn divmod(&self, other: &BigUint) -> (BigUint, BigUint) {
+ if other.is_zero() { fail }
+ if self.is_zero() { return (Zero::zero(), Zero::zero()); }
+ if *other == One::one() { return (copy *self, Zero::zero()); }
+
+ match self.cmp(other) {
+ s if s < 0 => return (Zero::zero(), copy *self),
+ 0 => return (One::one(), Zero::zero()),
+ _ => {} // Do nothing
+ }
+
+ let mut shift = 0;
+ let mut n = other.data.last();
+ while n < (1 << BigDigit::bits - 2) {
+ n <<= 1;
+ shift += 1;
+ }
+ assert shift < BigDigit::bits;
+ let (d, m) = divmod_inner(self << shift, other << shift);
+ return (d, m >> shift);
+
+ pure fn divmod_inner(a: BigUint, b: BigUint) -> (BigUint, BigUint) {
+ let mut r = a;
+ let mut d = Zero::zero::<BigUint>();
+ let mut n = 1;
+ while r >= b {
+ let mut (d0, d_unit, b_unit) = div_estimate(&r, &b, n);
+ let mut prod = b * d0;
+ while prod > r {
+ d0 -= d_unit;
+ prod -= b_unit;
+ }
+ if d0.is_zero() {
+ n = 2;
+ loop;
+ }
+ n = 1;
+ d += d0;
+ r -= prod;
+ }
+ return (d, r);
+ }
+
+ pure fn div_estimate(a: &BigUint, b: &BigUint, n: uint)
+ -> (BigUint, BigUint, BigUint) {
+ if a.data.len() < n {
+ return (Zero::zero(), Zero::zero(), copy *a);
+ }
+
+ let an = vec::view(a.data, a.data.len() - n, a.data.len());
+ let bn = b.data.last();
+ let mut d = ~[];
+ let mut carry = 0;
+ for vec::rev_each(an) |elt| {
+ let ai = BigDigit::to_uint(carry, *elt);
+ let di = ai / (bn as uint);
+ assert di < BigDigit::base;
+ carry = (ai % (bn as uint)) as BigDigit;
+ d = ~[di as BigDigit] + d;
+ }
+
+ let shift = (a.data.len() - an.len()) - (b.data.len() - 1);
+ if shift == 0 {
+ return (BigUint::new(d), One::one(), copy *b);
+ }
+ return (BigUint::from_slice(d).shl_unit(shift),
+ One::one::<BigUint>().shl_unit(shift),
+ b.shl_unit(shift));
+ }
+ }
+
+ pure fn quot(&self, other: &BigUint) -> BigUint {
+ let (q, _) = self.quotrem(other);
+ return q;
+ }
+ pure fn rem(&self, other: &BigUint) -> BigUint {
+ let (_, r) = self.quotrem(other);
+ return r;
+ }
+ pure fn quotrem(&self, other: &BigUint) -> (BigUint, BigUint) {
+ self.divmod(other)
+ }
+
+ pure fn is_zero(&self) -> bool { self.data.is_empty() }
+ pure fn is_not_zero(&self) -> bool { self.data.is_not_empty() }
+ pure fn is_positive(&self) -> bool { self.is_not_zero() }
+ pure fn is_negative(&self) -> bool { false }
+ pure fn is_nonpositive(&self) -> bool { self.is_zero() }
+ pure fn is_nonnegative(&self) -> bool { true }
+
+ pure fn to_uint(&self) -> uint {
+ match self.data.len() {
+ 0 => 0,
+ 1 => self.data[0] as uint,
+ 2 => BigDigit::to_uint(self.data[1], self.data[0]),
+ _ => uint::max_value
+ }
+ }
+
+ pure fn to_str_radix(&self, radix: uint) -> ~str {
+ assert 1 < radix && radix <= 16;
+ let (base, max_len) = get_radix_base(radix);
+ if base == BigDigit::base {
+ return fill_concat(self.data, radix, max_len)
+ }
+ return fill_concat(convert_base(copy *self, base), radix, max_len);
+
+ pure fn convert_base(n: BigUint, base: uint) -> ~[BigDigit] {
+ let divider = BigUint::from_uint(base);
+ let mut result = ~[];
+ let mut r = n;
+ while r > divider {
+ let (d, r0) = r.divmod(÷r);
+ result += [r0.to_uint() as BigDigit];
+ r = d;
+ }
+ if r.is_not_zero() {
+ result += [r.to_uint() as BigDigit];
+ }
+ return result;
+ }
+
+ pure fn fill_concat(v: &[BigDigit], radix: uint, l: uint) -> ~str {
+ if v.is_empty() { return ~"0" }
+ str::trim_left_chars(str::concat(vec::reversed(v).map(|n| {
+ let s = uint::to_str(*n as uint, radix);
+ str::from_chars(vec::from_elem(l - s.len(), '0')) + s
+ })), ['0'])
+ }
+ }
+
+ priv pure fn shl_unit(self, n_unit: uint) -> BigUint {
+ if n_unit == 0 || self.is_zero() { return self; }
+
+ return BigUint::new(vec::from_elem(n_unit, 0) + self.data);
+ }
+
+ priv pure fn shl_bits(self, n_bits: uint) -> BigUint {
+ if n_bits == 0 || self.is_zero() { return self; }
+
+ let mut carry = 0;
+ let shifted = do vec::map(self.data) |elem| {
+ let (hi, lo) = BigDigit::from_uint(
+ (*elem as uint) << n_bits | (carry as uint)
+ );
+ carry = hi;
+ lo
+ };
+ if carry == 0 { return BigUint::new(shifted); }
+ return BigUint::new(shifted + [carry]);
+ }
+
+ priv pure fn shr_unit(self, n_unit: uint) -> BigUint {
+ if n_unit == 0 { return self; }
+ if self.data.len() < n_unit { return Zero::zero(); }
+ return BigUint::from_slice(
+ vec::view(self.data, n_unit, self.data.len())
+ );
+ }
+
+ priv pure fn shr_bits(self, n_bits: uint) -> BigUint {
+ if n_bits == 0 || self.data.is_empty() { return self; }
+
+ let mut borrow = 0;
+ let mut shifted = ~[];
+ for vec::rev_each(self.data) |elem| {
+ shifted = ~[(*elem >> n_bits) | borrow] + shifted;
+ borrow = *elem << (uint::bits - n_bits);
+ }
+ return BigUint::new(shifted);
+ }
+ }
+
+ priv pure fn get_radix_base(radix: uint) -> (uint, uint) {
+ assert 1 < radix && radix <= 16;
+ match radix {
+ 2 => (4294967296, 32),
+ 3 => (3486784401, 20),
+ 4 => (4294967296, 16),
+ 5 => (1220703125, 13),
+ 6 => (2176782336, 12),
+ 7 => (1977326743, 11),
+ 8 => (1073741824, 10),
+ 9 => (3486784401, 10),
+ 10 => (1000000000, 9),
+ 11 => (2357947691, 9),
+ 12 => (429981696, 8),
+ 13 => (815730721, 8),
+ 14 => (1475789056, 8),
+ 15 => (2562890625, 8),
+ 16 => (4294967296, 8),
+ _ => fail
+ }
+ }
+
+ /// A Sign is a BigInt's composing element.
+ pub enum Sign { Minus, Zero, Plus }
+
+ impl Sign : Eq {
+ pure fn eq(&self, other: &Sign) -> bool { self.cmp(other) == 0 }
+ pure fn ne(&self, other: &Sign) -> bool { self.cmp(other) != 0 }
+ }
+
+ impl Sign : Ord {
+ pure fn lt(&self, other: &Sign) -> bool { self.cmp(other) < 0 }
+ pure fn le(&self, other: &Sign) -> bool { self.cmp(other) <= 0 }
+ pure fn ge(&self, other: &Sign) -> bool { self.cmp(other) >= 0 }
+ pure fn gt(&self, other: &Sign) -> bool { self.cmp(other) > 0 }
+ }
+
+ pub impl Sign {
+ /// Compare two Sign.
+ pure fn cmp(&self, other: &Sign) -> int {
+ match (*self, *other) {
+ (Minus, Minus) | (Zero, Zero) | (Plus, Plus) => 0,
+ (Minus, Zero) | (Minus, Plus) | (Zero, Plus) => -1,
+ _ => 1
+ }
+ }
+
+ /// Negate Sign value.
+ pure fn neg(&self) -> Sign {
+ match *self {
+ Minus => Plus,
+ Zero => Zero,
+ Plus => Minus
+ }
+ }
+ }
+
+ /// A big signed integer type.
+ pub struct BigInt {
+ priv sign: Sign,
+ priv data: BigUint
+ }
+
+ impl BigInt : Eq {
+ pure fn eq(&self, other: &BigInt) -> bool { self.cmp(other) == 0 }
+ pure fn ne(&self, other: &BigInt) -> bool { self.cmp(other) != 0 }
+ }
+
+ impl BigInt : Ord {
+ pure fn lt(&self, other: &BigInt) -> bool { self.cmp(other) < 0 }
+ pure fn le(&self, other: &BigInt) -> bool { self.cmp(other) <= 0 }
+ pure fn ge(&self, other: &BigInt) -> bool { self.cmp(other) >= 0 }
+ pure fn gt(&self, other: &BigInt) -> bool { self.cmp(other) > 0 }
+ }
+
+ impl BigInt : ToStr {
+ pure fn to_str() -> ~str { self.to_str_radix(10) }
+ }
+
+ impl BigInt : from_str::FromStr {
+ static pure fn from_str(s: &str) -> Option<BigInt> {
+ BigInt::from_str_radix(s, 10)
+ }
+ }
+
+ impl BigInt : Shl<uint, BigInt> {
+ pure fn shl(&self, rhs: &uint) -> BigInt {
+ BigInt::from_biguint(self.sign, self.data << *rhs)
+ }
+ }
+
+ impl BigInt : Shr<uint, BigInt> {
+ pure fn shr(&self, rhs: &uint) -> BigInt {
+ BigInt::from_biguint(self.sign, self.data >> *rhs)
+ }
+ }
+
+ impl BigInt : Zero {
+ static pub pure fn zero() -> BigInt {
+ BigInt::from_biguint(Zero, Zero::zero())
+ }
+ }
+
+ impl BigInt : One {
+ static pub pure fn one() -> BigInt {
+ BigInt::from_biguint(Plus, One::one())
+ }
+ }
+
+ impl BigInt : Num {
+ pure fn add(&self, other: &BigInt) -> BigInt {
+ match (self.sign, other.sign) {
+ (Zero, _) => copy *other,
+ (_, Zero) => copy *self,
+ (Plus, Plus) => BigInt::from_biguint(Plus,
+ self.data + other.data),
+ (Plus, Minus) => self - (-*other),
+ (Minus, Plus) => other - (-*self),
+ (Minus, Minus) => -((-self) + (-*other))
+ }
+ }
+ pure fn sub(&self, other: &BigInt) -> BigInt {
+ match (self.sign, other.sign) {
+ (Zero, _) => -other,
+ (_, Zero) => copy *self,
+ (Plus, Plus) => match self.data.cmp(&other.data) {
+ s if s < 0 =>
+ BigInt::from_biguint(Minus, other.data - self.data),
+ s if s > 0 =>
+ BigInt::from_biguint(Plus, self.data - other.data),
+ _ =>
+ Zero::zero()
+ },
+ (Plus, Minus) => self + (-*other),
+ (Minus, Plus) => -((-self) + *other),
+ (Minus, Minus) => (-other) - (-*self)
+ }
+ }
+ pure fn mul(&self, other: &BigInt) -> BigInt {
+ match (self.sign, other.sign) {
+ (Zero, _) | (_, Zero) => Zero::zero(),
+ (Plus, Plus) | (Minus, Minus) => {
+ BigInt::from_biguint(Plus, self.data * other.data)
+ },
+ (Plus, Minus) | (Minus, Plus) => {
+ BigInt::from_biguint(Minus, self.data * other.data)
+ }
+ }
+ }
+ pure fn div(&self, other: &BigInt) -> BigInt {
+ let (d, _) = self.divmod(other);
+ return d;
+ }
+ pure fn modulo(&self, other: &BigInt) -> BigInt {
+ let (_, m) = self.divmod(other);
+ return m;
+ }
+ pure fn neg(&self) -> BigInt {
+ BigInt::from_biguint(self.sign.neg(), copy self.data)
+ }
+
+ pure fn to_int(&self) -> int {
+ match self.sign {
+ Plus => uint::min(self.to_uint(), int::max_value as uint) as int,
+ Zero => 0,
+ Minus => uint::min((-self).to_uint(),
+ (int::max_value as uint) + 1) as int
+ }
+ }
+
+ static pure fn from_int(n: int) -> BigInt {
+ if n > 0 {
+ return BigInt::from_biguint(Plus, BigUint::from_uint(n as uint));
+ }
+ if n < 0 {
+ return BigInt::from_biguint(
+ Minus, BigUint::from_uint(uint::max_value - (n as uint) + 1)
+ );
+ }
+ return Zero::zero();
+ }
+ }
+
+ pub impl BigInt {
+ /// Creates and initializes an BigInt.
+ static pub pure fn new(sign: Sign, v: ~[BigDigit]) -> BigInt {
+ BigInt::from_biguint(sign, BigUint::new(v))
+ }
+
+ /// Creates and initializes an BigInt.
+ static pub pure fn from_biguint(sign: Sign, data: BigUint) -> BigInt {
+ if sign == Zero || data.is_zero() {
+ return BigInt { sign: Zero, data: Zero::zero() };
+ }
+ return BigInt { sign: sign, data: data };
+ }
+
+ /// Creates and initializes an BigInt.
+ static pub pure fn from_uint(n: uint) -> BigInt {
+ if n == 0 { return Zero::zero(); }
+ return BigInt::from_biguint(Plus, BigUint::from_uint(n));
+ }
+
+ /// Creates and initializes an BigInt.
+ static pub pure fn from_slice(sign: Sign, slice: &[BigDigit]) -> BigInt {
+ BigInt::from_biguint(sign, BigUint::from_slice(slice))
+ }
+
+ /// Creates and initializes an BigInt.
+ static pub pure fn from_str_radix(s: &str, radix: uint)
+ -> Option<BigInt> {
+ BigInt::parse_bytes(str::to_bytes(s), radix)
+ }
+
+ /// Creates and initializes an BigInt.
+ static pub pure fn parse_bytes(buf: &[u8], radix: uint)
+ -> Option<BigInt> {
+ if buf.is_empty() { return None; }
+ let mut sign = Plus;
+ let mut start = 0;
+ if buf[0] == ('-' as u8) {
+ sign = Minus;
+ start = 1;
+ }
+ return BigUint::parse_bytes(vec::view(buf, start, buf.len()), radix)
+ .map(|bu| BigInt::from_biguint(sign, *bu));
+ }
+
+ pure fn abs(&self) -> BigInt {
+ BigInt::from_biguint(Plus, copy self.data)
+ }
+
+ pure fn cmp(&self, other: &BigInt) -> int {
+ let ss = self.sign, os = other.sign;
+ if ss < os { return -1; }
+ if ss > os { return 1; }
+
+ assert ss == os;
+ match ss {
+ Zero => 0,
+ Plus => self.data.cmp(&other.data),
+ Minus => self.data.cmp(&other.data).neg(),
+ }
+ }
+
+ pure fn divmod(&self, other: &BigInt) -> (BigInt, BigInt) {
+ // m.sign == other.sign
+ let (d_ui, m_ui) = self.data.divmod(&other.data);
+ let d = BigInt::from_biguint(Plus, d_ui),
+ m = BigInt::from_biguint(Plus, m_ui);
+ match (self.sign, other.sign) {
+ (_, Zero) => fail,
+ (Plus, Plus) | (Zero, Plus) => (d, m),
+ (Plus, Minus) | (Zero, Minus) => if m.is_zero() {
+ (-d, Zero::zero())
+ } else {
+ (-d - One::one(), m + *other)
+ },
+ (Minus, Plus) => if m.is_zero() {
+ (-d, Zero::zero())
+ } else {
+ (-d - One::one(), other - m)
+ },
+ (Minus, Minus) => (d, -m)
+ }
+ }
+
+ pure fn quot(&self, other: &BigInt) -> BigInt {
+ let (q, _) = self.quotrem(other);
+ return q;
+ }
+ pure fn rem(&self, other: &BigInt) -> BigInt {
+ let (_, r) = self.quotrem(other);
+ return r;
+ }
+
+ pure fn quotrem(&self, other: &BigInt) -> (BigInt, BigInt) {
+ // r.sign == self.sign
+ let (q_ui, r_ui) = self.data.quotrem(&other.data);
+ let q = BigInt::from_biguint(Plus, q_ui);
+ let r = BigInt::from_biguint(Plus, r_ui);
+ match (self.sign, other.sign) {
+ (_, Zero) => fail,
+ (Plus, Plus) | (Zero, Plus) => ( q, r),
+ (Plus, Minus) | (Zero, Minus) => (-q, r),
+ (Minus, Plus) => (-q, -r),
+ (Minus, Minus) => ( q, -r)
+ }
+ }
+
+ pure fn is_zero(&self) -> bool { self.sign == Zero }
+ pure fn is_not_zero(&self) -> bool { self.sign != Zero }
+ pure fn is_positive(&self) -> bool { self.sign == Plus }
+ pure fn is_negative(&self) -> bool { self.sign == Minus }
+ pure fn is_nonpositive(&self) -> bool { self.sign != Plus }
+ pure fn is_nonnegative(&self) -> bool { self.sign != Minus }
+
+ pure fn to_uint(&self) -> uint {
+ match self.sign {
+ Plus => self.data.to_uint(),
+ Zero => 0,
+ Minus => 0
+ }
+ }
+
+ pure fn to_str_radix(&self, radix: uint) -> ~str {
+ match self.sign {
+ Plus => self.data.to_str_radix(radix),
+ Zero => ~"0",
+ Minus => ~"-" + self.data.to_str_radix(radix)
+ }
+ }
+ }
+
+ #[cfg(test)]
+ mod biguint_tests {
++
++ use core::*;
++ use core::num::{Num, Zero, One};
++ use super::{BigInt, BigUint, BigDigit};
++
+ #[test]
+ fn test_from_slice() {
+ fn check(slice: &[BigDigit], data: &[BigDigit]) {
+ assert data == BigUint::from_slice(slice).data;
+ }
+ check(~[1], ~[1]);
+ check(~[0, 0, 0], ~[]);
+ check(~[1, 2, 0, 0], ~[1, 2]);
+ check(~[0, 0, 1, 2], ~[0, 0, 1, 2]);
+ check(~[0, 0, 1, 2, 0, 0], ~[0, 0, 1, 2]);
+ check(~[-1], ~[-1]);
+ }
+
+ #[test]
+ fn test_cmp() {
+ let data = [ &[], &[1], &[2], &[-1], &[0, 1], &[2, 1], &[1, 1, 1] ]
+ .map(|v| BigUint::from_slice(*v));
+ for data.eachi |i, ni| {
+ for vec::view(data, i, data.len()).eachi |j0, nj| {
+ let j = j0 + i;
+ if i == j {
+ assert ni.cmp(nj) == 0;
+ assert nj.cmp(ni) == 0;
+ assert ni == nj;
+ assert !(ni != nj);
+ assert ni <= nj;
+ assert ni >= nj;
+ assert !(ni < nj);
+ assert !(ni > nj);
+ } else {
+ assert ni.cmp(nj) < 0;
+ assert nj.cmp(ni) > 0;
+
+ assert !(ni == nj);
+ assert ni != nj;
+
+ assert ni <= nj;
+ assert !(ni >= nj);
+ assert ni < nj;
+ assert !(ni > nj);
+
+ assert !(nj <= ni);
+ assert nj >= ni;
+ assert !(nj < ni);
+ assert nj > ni;
+ }
+ }
+ }
+ }
+
+ #[test]
+ fn test_shl() {
+ fn check(v: ~[BigDigit], shift: uint, ans: ~[BigDigit]) {
+ assert BigUint::new(v) << shift == BigUint::new(ans);
+ }
+
+ check(~[], 3, ~[]);
+ check(~[1, 1, 1], 3, ~[1 << 3, 1 << 3, 1 << 3]);
+ check(~[1 << (BigDigit::bits - 2)], 2, ~[0, 1]);
+ check(~[1 << (BigDigit::bits - 2)], 3, ~[0, 2]);
+ check(~[1 << (BigDigit::bits - 2)], 3 + BigDigit::bits, ~[0, 0, 2]);
+ check(~[0x7654_3210, 0xfedc_ba98, 0x7654_3210, 0xfedc_ba98], 4,
+ ~[0x6543_2100, 0xedcb_a987, 0x6543_210f, 0xedcb_a987, 0xf]);
+ check(~[0x2222_1111, 0x4444_3333, 0x6666_5555, 0x8888_7777], 16,
+ ~[0x1111_0000, 0x3333_2222, 0x5555_4444, 0x7777_6666, 0x8888]);
+ }
+
+ #[test]
+ fn test_shr() {
+ fn check(v: ~[BigDigit], shift: uint, ans: ~[BigDigit]) {
+ assert BigUint::new(v) >> shift == BigUint::new(ans);
+ }
+
+ check(~[], 3, ~[]);
+ check(~[1, 1, 1], 3,
+ ~[1 << (BigDigit::bits - 3), 1 << (BigDigit::bits - 3)]);
+ check(~[1 << 2], 2, ~[1]);
+ check(~[1, 2], 3, ~[1 << (BigDigit::bits - 2)]);
+ check(~[1, 1, 2], 3 + BigDigit::bits, ~[1 << (BigDigit::bits - 2)]);
+ check(~[0x6543_2100, 0xedcb_a987, 0x6543_210f, 0xedcb_a987, 0xf], 4,
+ ~[0x7654_3210, 0xfedc_ba98, 0x7654_3210, 0xfedc_ba98]);
+ check(~[0x1111_0000, 0x3333_2222, 0x5555_4444, 0x7777_6666, 0x8888],
+ 16,
+ ~[0x2222_1111, 0x4444_3333, 0x6666_5555, 0x8888_7777]);
+ }
+
+ #[test]
+ fn test_convert_int() {
+ fn check(v: ~[BigDigit], i: int) {
+ let b = BigUint::new(v);
+ assert b == Num::from_int(i);
+ assert b.to_int() == i;
+ }
+
+ check(~[], 0);
+ check(~[1], 1);
+ check(~[-1], (uint::max_value >> BigDigit::bits) as int);
+ check(~[ 0, 1], ((uint::max_value >> BigDigit::bits) + 1) as int);
+ check(~[-1, -1 >> 1], int::max_value);
+
+ assert BigUint::new(~[0, -1]).to_int() == int::max_value;
+ assert BigUint::new(~[0, 0, 1]).to_int() == int::max_value;
+ assert BigUint::new(~[0, 0, -1]).to_int() == int::max_value;
+ }
+
+ #[test]
+ fn test_convert_uint() {
+ fn check(v: ~[BigDigit], u: uint) {
+ let b = BigUint::new(v);
+ assert b == BigUint::from_uint(u);
+ assert b.to_uint() == u;
+ }
+
+ check(~[], 0);
+ check(~[ 1], 1);
+ check(~[-1], uint::max_value >> BigDigit::bits);
+ check(~[ 0, 1], (uint::max_value >> BigDigit::bits) + 1);
+ check(~[ 0, -1], uint::max_value << BigDigit::bits);
+ check(~[-1, -1], uint::max_value);
+
+ assert BigUint::new(~[0, 0, 1]).to_uint() == uint::max_value;
+ assert BigUint::new(~[0, 0, -1]).to_uint() == uint::max_value;
+ }
+
+ const sum_triples: &[(&[BigDigit], &[BigDigit], &[BigDigit])] = &[
+ (&[], &[], &[]),
+ (&[], &[ 1], &[ 1]),
+ (&[ 1], &[ 1], &[ 2]),
+ (&[ 1], &[ 1, 1], &[ 2, 1]),
+ (&[ 1], &[-1], &[ 0, 1]),
+ (&[ 1], &[-1, -1], &[ 0, 0, 1]),
+ (&[-1, -1], &[-1, -1], &[-2, -1, 1]),
+ (&[ 1, 1, 1], &[-1, -1], &[ 0, 1, 2]),
+ (&[ 2, 2, 1], &[-1, -2], &[ 1, 1, 2])
+ ];
+
+ #[test]
+ fn test_add() {
+ for sum_triples.each |elm| {
+ let (aVec, bVec, cVec) = *elm;
+ let a = BigUint::from_slice(aVec);
+ let b = BigUint::from_slice(bVec);
+ let c = BigUint::from_slice(cVec);
+
+ assert a + b == c;
+ assert b + a == c;
+ }
+ }
+
+ #[test]
+ fn test_sub() {
+ for sum_triples.each |elm| {
+ let (aVec, bVec, cVec) = *elm;
+ let a = BigUint::from_slice(aVec);
+ let b = BigUint::from_slice(bVec);
+ let c = BigUint::from_slice(cVec);
+
+ assert c - a == b;
+ assert c - b == a;
+ }
+ }
+
+ const mul_triples: &[(&[BigDigit], &[BigDigit], &[BigDigit])] = &[
+ (&[], &[], &[]),
+ (&[], &[ 1], &[]),
+ (&[ 2], &[], &[]),
+ (&[ 1], &[ 1], &[1]),
+ (&[ 2], &[ 3], &[ 6]),
+ (&[ 1], &[ 1, 1, 1], &[1, 1, 1]),
+ (&[ 1, 2, 3], &[ 3], &[ 3, 6, 9]),
+ (&[ 1, 1, 1], &[-1], &[-1, -1, -1]),
+ (&[ 1, 2, 3], &[-1], &[-1, -2, -2, 2]),
+ (&[ 1, 2, 3, 4], &[-1], &[-1, -2, -2, -2, 3]),
+ (&[-1], &[-1], &[ 1, -2]),
+ (&[-1, -1], &[-1], &[ 1, -1, -2]),
+ (&[-1, -1, -1], &[-1], &[ 1, -1, -1, -2]),
+ (&[-1, -1, -1, -1], &[-1], &[ 1, -1, -1, -1, -2]),
+ (&[-1/2 + 1], &[ 2], &[ 0, 1]),
+ (&[0, -1/2 + 1], &[ 2], &[ 0, 0, 1]),
+ (&[ 1, 2], &[ 1, 2, 3], &[1, 4, 7, 6]),
+ (&[-1, -1], &[-1, -1, -1], &[1, 0, -1, -2, -1]),
+ (&[-1, -1, -1], &[-1, -1, -1, -1], &[1, 0, 0, -1, -2, -1, -1]),
+ (&[ 0, 0, 1], &[ 1, 2, 3], &[0, 0, 1, 2, 3]),
+ (&[ 0, 0, 1], &[ 0, 0, 0, 1], &[0, 0, 0, 0, 0, 1])
+ ];
+
+ const divmod_quadruples: &[(&[BigDigit], &[BigDigit],
+ &[BigDigit], &[BigDigit])]
+ = &[
+ (&[ 1], &[ 2], &[], &[1]),
+ (&[ 1, 1], &[ 2], &[-1/2+1], &[1]),
+ (&[ 1, 1, 1], &[ 2], &[-1/2+1, -1/2+1], &[1]),
+ (&[ 0, 1], &[-1], &[1], &[1]),
+ (&[-1, -1], &[-2], &[2, 1], &[3])
+ ];
+
+ #[test]
+ fn test_mul() {
+ for mul_triples.each |elm| {
+ let (aVec, bVec, cVec) = *elm;
+ let a = BigUint::from_slice(aVec);
+ let b = BigUint::from_slice(bVec);
+ let c = BigUint::from_slice(cVec);
+
+ assert a * b == c;
+ assert b * a == c;
+ }
+
+ for divmod_quadruples.each |elm| {
+ let (aVec, bVec, cVec, dVec) = *elm;
+ let a = BigUint::from_slice(aVec);
+ let b = BigUint::from_slice(bVec);
+ let c = BigUint::from_slice(cVec);
+ let d = BigUint::from_slice(dVec);
+
+ assert a == b * c + d;
+ assert a == c * b + d;
+ }
+ }
+
+ #[test]
+ fn test_divmod() {
+ for mul_triples.each |elm| {
+ let (aVec, bVec, cVec) = *elm;
+ let a = BigUint::from_slice(aVec);
+ let b = BigUint::from_slice(bVec);
+ let c = BigUint::from_slice(cVec);
+
+ if a.is_not_zero() {
+ assert c.divmod(&a) == (b, Zero::zero());
+ }
+ if b.is_not_zero() {
+ assert c.divmod(&b) == (a, Zero::zero());
+ }
+ }
+
+ for divmod_quadruples.each |elm| {
+ let (aVec, bVec, cVec, dVec) = *elm;
+ let a = BigUint::from_slice(aVec);
+ let b = BigUint::from_slice(bVec);
+ let c = BigUint::from_slice(cVec);
+ let d = BigUint::from_slice(dVec);
+
+ if b.is_not_zero() { assert a.divmod(&b) == (c, d); }
+ }
+ }
+
+ fn to_str_pairs() -> ~[ (BigUint, ~[(uint, ~str)]) ] {
+ ~[( Zero::zero(), ~[
+ (2, ~"0"), (3, ~"0")
+ ]), ( BigUint::from_slice([ 0xff ]), ~[
+ (2, ~"11111111"),
+ (3, ~"100110"),
+ (4, ~"3333"),
+ (5, ~"2010"),
+ (6, ~"1103"),
+ (7, ~"513"),
+ (8, ~"377"),
+ (9, ~"313"),
+ (10, ~"255"),
+ (11, ~"212"),
+ (12, ~"193"),
+ (13, ~"168"),
+ (14, ~"143"),
+ (15, ~"120"),
+ (16, ~"ff")
+ ]), ( BigUint::from_slice([ 0xfff ]), ~[
+ (2, ~"111111111111"),
+ (4, ~"333333"),
+ (16, ~"fff")
+ ]), ( BigUint::from_slice([ 1, 2 ]), ~[
+ (2, ~"10" + str::from_chars(vec::from_elem(31, '0')) + "1"),
+ (4, ~"2" + str::from_chars(vec::from_elem(15, '0')) + "1"),
+ (10, ~"8589934593"),
+ (16, ~"2" + str::from_chars(vec::from_elem(7, '0')) + "1")
+ ]), (BigUint::from_slice([ 1, 2, 3 ]), ~[
+ (2, ~"11" + str::from_chars(vec::from_elem(30, '0')) + "10" +
+ str::from_chars(vec::from_elem(31, '0')) + "1"),
+ (4, ~"3" + str::from_chars(vec::from_elem(15, '0')) + "2" +
+ str::from_chars(vec::from_elem(15, '0')) + "1"),
+ (10, ~"55340232229718589441"),
+ (16, ~"3" + str::from_chars(vec::from_elem(7, '0')) + "2" +
+ str::from_chars(vec::from_elem(7, '0')) + "1")
+ ])]
+ }
+
+ #[test]
+ fn test_to_str_radix() {
+ for to_str_pairs().each |num_pair| {
+ let &(n, rs) = num_pair;
+ for rs.each |str_pair| {
+ let &(radix, str) = str_pair;
+ assert n.to_str_radix(radix) == str;
+ }
+ }
+ }
+
+ #[test]
+ fn test_from_str_radix() {
+ for to_str_pairs().each |num_pair| {
+ let &(n, rs) = num_pair;
+ for rs.each |str_pair| {
+ let &(radix, str) = str_pair;
+ assert Some(n) == BigUint::from_str_radix(str, radix);
+ }
+ }
+
+ assert BigUint::from_str_radix(~"Z", 10) == None;
+ assert BigUint::from_str_radix(~"_", 2) == None;
+ assert BigUint::from_str_radix(~"-1", 10) == None;
+ }
+
+ #[test]
+ fn test_factor() {
+ fn factor(n: uint) -> BigUint {
+ let mut f= One::one::<BigUint>();
+ for uint::range(2, n + 1) |i| {
+ f *= BigUint::from_uint(i);
+ }
+ return f;
+ }
+
+ fn check(n: uint, s: &str) {
+ let n = factor(n);
+ let ans = match BigUint::from_str_radix(s, 10) {
+ Some(x) => x, None => fail
+ };
+ assert n == ans;
+ }
+
+ check(3, "6");
+ check(10, "3628800");
+ check(20, "2432902008176640000");
+ check(30, "265252859812191058636308480000000");
+ }
+ }
+
+ #[cfg(test)]
+ mod bigint_tests {
++
++ use core::*;
++ use core::num::{Num, Zero, One};
++ use super::{BigInt, BigUint, BigDigit};
++
+ #[test]
+ fn test_from_biguint() {
+ fn check(inp_s: Sign, inp_n: uint, ans_s: Sign, ans_n: uint) {
+ let inp = BigInt::from_biguint(inp_s, BigUint::from_uint(inp_n));
+ let ans = BigInt { sign: ans_s, data: BigUint::from_uint(ans_n)};
+ assert inp == ans;
+ }
+ check(Plus, 1, Plus, 1);
+ check(Plus, 0, Zero, 0);
+ check(Minus, 1, Minus, 1);
+ check(Zero, 1, Zero, 0);
+ }
+
+ #[test]
+ fn test_cmp() {
+ let vs = [ &[2], &[1, 1], &[2, 1], &[1, 1, 1] ];
+ let mut nums = vec::reversed(vs)
+ .map(|s| BigInt::from_slice(Minus, *s));
+ nums.push(Zero::zero());
+ nums.push_all_move(vs.map(|s| BigInt::from_slice(Plus, *s)));
+
+ for nums.eachi |i, ni| {
+ for vec::view(nums, i, nums.len()).eachi |j0, nj| {
+ let j = i + j0;
+ if i == j {
+ assert ni.cmp(nj) == 0;
+ assert nj.cmp(ni) == 0;
+ assert ni == nj;
+ assert !(ni != nj);
+ assert ni <= nj;
+ assert ni >= nj;
+ assert !(ni < nj);
+ assert !(ni > nj);
+ } else {
+ assert ni.cmp(nj) < 0;
+ assert nj.cmp(ni) > 0;
+
+ assert !(ni == nj);
+ assert ni != nj;
+
+ assert ni <= nj;
+ assert !(ni >= nj);
+ assert ni < nj;
+ assert !(ni > nj);
+
+ assert !(nj <= ni);
+ assert nj >= ni;
+ assert !(nj < ni);
+ assert nj > ni;
+ }
+ }
+ }
+ }
+
+ #[test]
+ fn test_convert_int() {
+ fn check(b: BigInt, i: int) {
+ assert b == Num::from_int(i);
+ assert b.to_int() == i;
+ }
+
+ check(Zero::zero(), 0);
+ check(One::one(), 1);
+ check(BigInt::from_biguint(
+ Plus, BigUint::from_uint(int::max_value as uint)
+ ), int::max_value);
+
+ assert BigInt::from_biguint(
+ Plus, BigUint::from_uint(int::max_value as uint + 1)
+ ).to_int() == int::max_value;
+ assert BigInt::from_biguint(
+ Plus, BigUint::new(~[1, 2, 3])
+ ).to_int() == int::max_value;
+
+ check(BigInt::from_biguint(
+ Minus, BigUint::from_uint(-int::min_value as uint)
+ ), int::min_value);
+ assert BigInt::from_biguint(
+ Minus, BigUint::from_uint(-int::min_value as uint + 1)
+ ).to_int() == int::min_value;
+ assert BigInt::from_biguint(
+ Minus, BigUint::new(~[1, 2, 3])
+ ).to_int() == int::min_value;
+ }
+
+ #[test]
+ fn test_convert_uint() {
+ fn check(b: BigInt, u: uint) {
+ assert b == BigInt::from_uint(u);
+ assert b.to_uint() == u;
+ }
+
+ check(Zero::zero(), 0);
+ check(One::one(), 1);
+
+ check(
+ BigInt::from_biguint(Plus, BigUint::from_uint(uint::max_value)),
+ uint::max_value);
+ assert BigInt::from_biguint(
+ Plus, BigUint::new(~[1, 2, 3])
+ ).to_uint() == uint::max_value;
+
+ assert BigInt::from_biguint(
+ Minus, BigUint::from_uint(uint::max_value)
+ ).to_uint() == 0;
+ assert BigInt::from_biguint(
+ Minus, BigUint::new(~[1, 2, 3])
+ ).to_uint() == 0;
+ }
+
+ const sum_triples: &[(&[BigDigit], &[BigDigit], &[BigDigit])] = &[
+ (&[], &[], &[]),
+ (&[], &[ 1], &[ 1]),
+ (&[ 1], &[ 1], &[ 2]),
+ (&[ 1], &[ 1, 1], &[ 2, 1]),
+ (&[ 1], &[-1], &[ 0, 1]),
+ (&[ 1], &[-1, -1], &[ 0, 0, 1]),
+ (&[-1, -1], &[-1, -1], &[-2, -1, 1]),
+ (&[ 1, 1, 1], &[-1, -1], &[ 0, 1, 2]),
+ (&[ 2, 2, 1], &[-1, -2], &[ 1, 1, 2])
+ ];
+
+ #[test]
+ fn test_add() {
+ for sum_triples.each |elm| {
+ let (aVec, bVec, cVec) = *elm;
+ let a = BigInt::from_slice(Plus, aVec);
+ let b = BigInt::from_slice(Plus, bVec);
+ let c = BigInt::from_slice(Plus, cVec);
+
+ assert a + b == c;
+ assert b + a == c;
+ assert c + (-a) == b;
+ assert c + (-b) == a;
+ assert a + (-c) == (-b);
+ assert b + (-c) == (-a);
+ assert (-a) + (-b) == (-c);
+ assert a + (-a) == Zero::zero();
+ }
+ }
+
+ #[test]
+ fn test_sub() {
+ for sum_triples.each |elm| {
+ let (aVec, bVec, cVec) = *elm;
+ let a = BigInt::from_slice(Plus, aVec);
+ let b = BigInt::from_slice(Plus, bVec);
+ let c = BigInt::from_slice(Plus, cVec);
+
+ assert c - a == b;
+ assert c - b == a;
+ assert (-b) - a == (-c);
+ assert (-a) - b == (-c);
+ assert b - (-a) == c;
+ assert a - (-b) == c;
+ assert (-c) - (-a) == (-b);
+ assert a - a == Zero::zero();
+ }
+ }
+
+ const mul_triples: &[(&[BigDigit], &[BigDigit], &[BigDigit])] = &[
+ (&[], &[], &[]),
+ (&[], &[ 1], &[]),
+ (&[ 2], &[], &[]),
+ (&[ 1], &[ 1], &[1]),
+ (&[ 2], &[ 3], &[ 6]),
+ (&[ 1], &[ 1, 1, 1], &[1, 1, 1]),
+ (&[ 1, 2, 3], &[ 3], &[ 3, 6, 9]),
+ (&[ 1, 1, 1], &[-1], &[-1, -1, -1]),
+ (&[ 1, 2, 3], &[-1], &[-1, -2, -2, 2]),
+ (&[ 1, 2, 3, 4], &[-1], &[-1, -2, -2, -2, 3]),
+ (&[-1], &[-1], &[ 1, -2]),
+ (&[-1, -1], &[-1], &[ 1, -1, -2]),
+ (&[-1, -1, -1], &[-1], &[ 1, -1, -1, -2]),
+ (&[-1, -1, -1, -1], &[-1], &[ 1, -1, -1, -1, -2]),
+ (&[-1/2 + 1], &[ 2], &[ 0, 1]),
+ (&[0, -1/2 + 1], &[ 2], &[ 0, 0, 1]),
+ (&[ 1, 2], &[ 1, 2, 3], &[1, 4, 7, 6]),
+ (&[-1, -1], &[-1, -1, -1], &[1, 0, -1, -2, -1]),
+ (&[-1, -1, -1], &[-1, -1, -1, -1], &[1, 0, 0, -1, -2, -1, -1]),
+ (&[ 0, 0, 1], &[ 1, 2, 3], &[0, 0, 1, 2, 3]),
+ (&[ 0, 0, 1], &[ 0, 0, 0, 1], &[0, 0, 0, 0, 0, 1])
+ ];
+
+ const divmod_quadruples: &[(&[BigDigit], &[BigDigit],
+ &[BigDigit], &[BigDigit])]
+ = &[
+ (&[ 1], &[ 2], &[], &[1]),
+ (&[ 1, 1], &[ 2], &[-1/2+1], &[1]),
+ (&[ 1, 1, 1], &[ 2], &[-1/2+1, -1/2+1], &[1]),
+ (&[ 0, 1], &[-1], &[1], &[1]),
+ (&[-1, -1], &[-2], &[2, 1], &[3])
+ ];
+
+ #[test]
+ fn test_mul() {
+ for mul_triples.each |elm| {
+ let (aVec, bVec, cVec) = *elm;
+ let a = BigInt::from_slice(Plus, aVec);
+ let b = BigInt::from_slice(Plus, bVec);
+ let c = BigInt::from_slice(Plus, cVec);
+
+ assert a * b == c;
+ assert b * a == c;
+
+ assert (-a) * b == -c;
+ assert (-b) * a == -c;
+ }
+
+ for divmod_quadruples.each |elm| {
+ let (aVec, bVec, cVec, dVec) = *elm;
+ let a = BigInt::from_slice(Plus, aVec);
+ let b = BigInt::from_slice(Plus, bVec);
+ let c = BigInt::from_slice(Plus, cVec);
+ let d = BigInt::from_slice(Plus, dVec);
+
+ assert a == b * c + d;
+ assert a == c * b + d;
+ }
+ }
+
+ #[test]
+ fn test_divmod() {
+ fn check_sub(a: &BigInt, b: &BigInt, ans_d: &BigInt, ans_m: &BigInt) {
+ let (d, m) = a.divmod(b);
+ if m.is_not_zero() {
+ assert m.sign == b.sign;
+ }
+ assert m.abs() <= b.abs();
+ assert *a == b * d + m;
+ assert d == *ans_d;
+ assert m == *ans_m;
+ }
+
+ fn check(a: &BigInt, b: &BigInt, d: &BigInt, m: &BigInt) {
+ if m.is_zero() {
+ check_sub(a, b, d, m);
+ check_sub(a, &b.neg(), &d.neg(), m);
+ check_sub(&a.neg(), b, &d.neg(), m);
+ check_sub(&a.neg(), &b.neg(), d, m);
+ } else {
+ check_sub(a, b, d, m);
+ check_sub(a, &b.neg(), &(d.neg() - One::one()), &(m - *b));
+ check_sub(&a.neg(), b, &(d.neg() - One::one()), &(b - *m));
+ check_sub(&a.neg(), &b.neg(), d, &m.neg());
+ }
+ }
+
+ for mul_triples.each |elm| {
+ let (aVec, bVec, cVec) = *elm;
+ let a = BigInt::from_slice(Plus, aVec);
+ let b = BigInt::from_slice(Plus, bVec);
+ let c = BigInt::from_slice(Plus, cVec);
+
+ if a.is_not_zero() { check(&c, &a, &b, &Zero::zero()); }
+ if b.is_not_zero() { check(&c, &b, &a, &Zero::zero()); }
+ }
+
+ for divmod_quadruples.each |elm| {
+ let (aVec, bVec, cVec, dVec) = *elm;
+ let a = BigInt::from_slice(Plus, aVec);
+ let b = BigInt::from_slice(Plus, bVec);
+ let c = BigInt::from_slice(Plus, cVec);
+ let d = BigInt::from_slice(Plus, dVec);
+
+ if b.is_not_zero() {
+ check(&a, &b, &c, &d);
+ }
+ }
+ }
+
+
+ #[test]
+ fn test_quotrem() {
+ fn check_sub(a: &BigInt, b: &BigInt, ans_q: &BigInt, ans_r: &BigInt) {
+ let (q, r) = a.quotrem(b);
+ if r.is_not_zero() {
+ assert r.sign == a.sign;
+ }
+ assert r.abs() <= b.abs();
+ assert *a == b * q + r;
+ assert q == *ans_q;
+ assert r == *ans_r;
+ }
+
+ fn check(a: &BigInt, b: &BigInt, q: &BigInt, r: &BigInt) {
+ check_sub(a, b, q, r);
+ check_sub(a, &b.neg(), &q.neg(), r);
+ check_sub(&a.neg(), b, &q.neg(), &r.neg());
+ check_sub(&a.neg(), &b.neg(), q, &r.neg());
+ }
+ for mul_triples.each |elm| {
+ let (aVec, bVec, cVec) = *elm;
+ let a = BigInt::from_slice(Plus, aVec);
+ let b = BigInt::from_slice(Plus, bVec);
+ let c = BigInt::from_slice(Plus, cVec);
+
+ if a.is_not_zero() { check(&c, &a, &b, &Zero::zero()); }
+ if b.is_not_zero() { check(&c, &b, &a, &Zero::zero()); }
+ }
+
+ for divmod_quadruples.each |elm| {
+ let (aVec, bVec, cVec, dVec) = *elm;
+ let a = BigInt::from_slice(Plus, aVec);
+ let b = BigInt::from_slice(Plus, bVec);
+ let c = BigInt::from_slice(Plus, cVec);
+ let d = BigInt::from_slice(Plus, dVec);
+
+ if b.is_not_zero() {
+ check(&a, &b, &c, &d);
+ }
+ }
+ }
+
+ #[test]
+ fn test_to_str_radix() {
+ fn check(n: int, ans: &str) {
+ assert ans == Num::from_int::<BigInt>(n).to_str_radix(10);
+ }
+ check(10, "10");
+ check(1, "1");
+ check(0, "0");
+ check(-1, "-1");
+ check(-10, "-10");
+ }
+
+
+ #[test]
+ fn test_from_str_radix() {
+ fn check(s: &str, ans: Option<int>) {
+ let ans = ans.map(|&n| Num::from_int(n));
+ assert BigInt::from_str_radix(s, 10) == ans;
+ }
+ check("10", Some(10));
+ check("1", Some(1));
+ check("0", Some(0));
+ check("-1", Some(-1));
+ check("-10", Some(-10));
+ check("Z", None);
+ check("_", None);
+ }
+
+ #[test]
+ fn test_neg() {
+ assert -BigInt::new(Plus, ~[1, 1, 1]) ==
+ BigInt::new(Minus, ~[1, 1, 1]);
+ assert -BigInt::new(Minus, ~[1, 1, 1]) ==
+ BigInt::new(Plus, ~[1, 1, 1]);
+ assert -Zero::zero::<BigInt>() == Zero::zero::<BigInt>();
+ }
+ }
+