From 7504b3d87d6143661746d85c3c3e4052939b4e52 Mon Sep 17 00:00:00 2001 From: Bo Xu Date: Tue, 2 Dec 2014 13:06:22 -0800 Subject: Initial check in of big integer library, v2010.04.30 R=tsepez@chromium.org Review URL: https://codereview.chromium.org/773443004 --- third_party/bigint/BigIntegerUtils.cc | 50 +++++++++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 third_party/bigint/BigIntegerUtils.cc (limited to 'third_party/bigint/BigIntegerUtils.cc') diff --git a/third_party/bigint/BigIntegerUtils.cc b/third_party/bigint/BigIntegerUtils.cc new file mode 100644 index 0000000000..44073af652 --- /dev/null +++ b/third_party/bigint/BigIntegerUtils.cc @@ -0,0 +1,50 @@ +#include "BigIntegerUtils.hh" +#include "BigUnsignedInABase.hh" + +std::string bigUnsignedToString(const BigUnsigned &x) { + return std::string(BigUnsignedInABase(x, 10)); +} + +std::string bigIntegerToString(const BigInteger &x) { + return (x.getSign() == BigInteger::negative) + ? (std::string("-") + bigUnsignedToString(x.getMagnitude())) + : (bigUnsignedToString(x.getMagnitude())); +} + +BigUnsigned stringToBigUnsigned(const std::string &s) { + return BigUnsigned(BigUnsignedInABase(s, 10)); +} + +BigInteger stringToBigInteger(const std::string &s) { + // Recognize a sign followed by a BigUnsigned. + return (s[0] == '-') ? BigInteger(stringToBigUnsigned(s.substr(1, s.length() - 1)), BigInteger::negative) + : (s[0] == '+') ? BigInteger(stringToBigUnsigned(s.substr(1, s.length() - 1))) + : BigInteger(stringToBigUnsigned(s)); +} + +std::ostream &operator <<(std::ostream &os, const BigUnsigned &x) { + BigUnsignedInABase::Base base; + long osFlags = os.flags(); + if (osFlags & os.dec) + base = 10; + else if (osFlags & os.hex) { + base = 16; + if (osFlags & os.showbase) + os << "0x"; + } else if (osFlags & os.oct) { + base = 8; + if (osFlags & os.showbase) + os << '0'; + } else + throw "std::ostream << BigUnsigned: Could not determine the desired base from output-stream flags"; + std::string s = std::string(BigUnsignedInABase(x, base)); + os << s; + return os; +} + +std::ostream &operator <<(std::ostream &os, const BigInteger &x) { + if (x.getSign() == BigInteger::negative) + os << '-'; + os << x.getMagnitude(); + return os; +} -- cgit v1.2.3