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373148_0_0_18232.cpp
373148_0_0_18232.obj : error LNK2019: 无法解析的外部符号 "public: __thiscall BigNum::BigNum(class BigNum const &)" (??0BigNum@@QAE@ABV0@@Z) ，该符号在函数 "public: class BigNum __thiscall BigNum::operator*(class BigNum const &)const " (??DBigNum@@QBE?AV0@ABV0@@Z) 中被引用
373148_0_0_18232.exe : fatal error LNK1120: 1 个无法解析的外部命令