| Index: third_party/bigint/BigIntegerAlgorithms.cc
|
| diff --git a/third_party/bigint/BigIntegerAlgorithms.cc b/third_party/bigint/BigIntegerAlgorithms.cc
|
| deleted file mode 100644
|
| index 7edebda76a8e17de58dcb3476bc02e3d6be5a249..0000000000000000000000000000000000000000
|
| --- a/third_party/bigint/BigIntegerAlgorithms.cc
|
| +++ /dev/null
|
| @@ -1,70 +0,0 @@
|
| -#include "BigIntegerAlgorithms.hh"
|
| -
|
| -BigUnsigned gcd(BigUnsigned a, BigUnsigned b) {
|
| - BigUnsigned trash;
|
| - // Neat in-place alternating technique.
|
| - for (;;) {
|
| - if (b.isZero())
|
| - return a;
|
| - a.divideWithRemainder(b, trash);
|
| - if (a.isZero())
|
| - return b;
|
| - b.divideWithRemainder(a, trash);
|
| - }
|
| -}
|
| -
|
| -void extendedEuclidean(BigInteger m, BigInteger n,
|
| - BigInteger &g, BigInteger &r, BigInteger &s) {
|
| - if (&g == &r || &g == &s || &r == &s)
|
| - throw "BigInteger extendedEuclidean: Outputs are aliased";
|
| - BigInteger r1(1), s1(0), r2(0), s2(1), q;
|
| - /* Invariants:
|
| - * r1*m(orig) + s1*n(orig) == m(current)
|
| - * r2*m(orig) + s2*n(orig) == n(current) */
|
| - for (;;) {
|
| - if (n.isZero()) {
|
| - r = r1; s = s1; g = m;
|
| - return;
|
| - }
|
| - // Subtract q times the second invariant from the first invariant.
|
| - m.divideWithRemainder(n, q);
|
| - r1 -= q*r2; s1 -= q*s2;
|
| -
|
| - if (m.isZero()) {
|
| - r = r2; s = s2; g = n;
|
| - return;
|
| - }
|
| - // Subtract q times the first invariant from the second invariant.
|
| - n.divideWithRemainder(m, q);
|
| - r2 -= q*r1; s2 -= q*s1;
|
| - }
|
| -}
|
| -
|
| -BigUnsigned modinv(const BigInteger &x, const BigUnsigned &n) {
|
| - BigInteger g, r, s;
|
| - extendedEuclidean(x, n, g, r, s);
|
| - if (g == 1)
|
| - // r*x + s*n == 1, so r*x === 1 (mod n), so r is the answer.
|
| - return (r % n).getMagnitude(); // (r % n) will be nonnegative
|
| - else
|
| - throw "BigInteger modinv: x and n have a common factor";
|
| -}
|
| -
|
| -BigUnsigned modexp(const BigInteger &base, const BigUnsigned &exponent,
|
| - const BigUnsigned &modulus) {
|
| - BigUnsigned ans = 1, base2 = (base % modulus).getMagnitude();
|
| - BigUnsigned::Index i = exponent.bitLength();
|
| - // For each bit of the exponent, most to least significant...
|
| - while (i > 0) {
|
| - i--;
|
| - // Square.
|
| - ans *= ans;
|
| - ans %= modulus;
|
| - // And multiply if the bit is a 1.
|
| - if (exponent.getBit(i)) {
|
| - ans *= base2;
|
| - ans %= modulus;
|
| - }
|
| - }
|
| - return ans;
|
| -}
|
|
|