message: [Cleaning] Remove unused get/setcompact functions from zerocoin bignum
diff: @@ -303,71 +303,6 @@ public:
  return vch;
  }
  - // The "compact" format is a representation of a whole
  - // number N using an unsigned 32bit number similar to a
  - // floating point format.
  - // The most significant 8 bits are the unsigned exponent of base 256.
  - // This exponent can be thought of as "number of bytes of N".
  - // The lower 23 bits are the mantissa.
  - // Bit number 24 (0x800000) represents the sign of N.
  - // N = (-1^sign) * mantissa * 256^(exponent-3)
  - //
  - // Satoshi's original implementation used BN_bn2mpi() and BN_mpi2bn().
  - // MPI uses the most significant bit of the first byte as sign.
  - // Thus 0x1234560000 is compact (0x05123456)
  - // and 0xc0de000000 is compact (0x0600c0de)
  - // (0x05c0de00) would be -0x40de000000
  - //
  - // Bitcoin only uses this "compact" format for encoding difficulty
  - // targets, which are unsigned 256bit quantities. Thus, all the
  - // complexities of the sign bit and using base 256 are probably an
  - // implementation accident.
  - //
  - // This implementation directly uses shifts instead of going
  - // through an intermediate MPI representation.
  - CBigNum& SetCompact(unsigned int nCompact)
  - {
  - unsigned int nSize = nCompact >> 24;
  - bool fNegative =(nCompact & 0x00800000) != 0;
  - unsigned int nWord = nCompact & 0x007fffff;
  - if (nSize <= 3)
  - {
  - nWord >>= 8*(3-nSize);
  - BN_set_word(bn, nWord);
  - }
  - else
  - {
  - BN_set_word(bn, nWord);
  - BN_lshift(bn, bn, 8*(nSize-3));
  - }
  - BN_set_negative(bn, fNegative);
  - return *this;
  - }
  -
  - unsigned int GetCompact() const
  - {
  - unsigned int nSize = BN_num_bytes(bn);
  - unsigned int nCompact = 0;
  - if (nSize <= 3)
  - nCompact = BN_get_word(bn) << 8*(3-nSize);
  - else
  - {
  - CBigNum cbn;
  - BN_rshift(cbn.bn, bn, 8*(nSize-3));
  - nCompact = BN_get_word(cbn.bn);
  - }
  - // The 0x00800000 bit denotes the sign.
  - // Thus, if it is already set, divide the mantissa by 256 and increase the exponent.
  - if (nCompact & 0x00800000)
  - {
  - nCompact >>= 8;
  - nSize++;
  - }
  - nCompact |= nSize << 24;
  - nCompact |= (BN_is_negative(bn) ? 0x00800000 : 0);
  - return nCompact;
  - }
  -
  void SetDec(const std::string& str)
  {
  BN_dec2bn(&bn, str.c_str());
  