Compilare: user.cpp: In member function 'BigInt& BigInt::operator=(const BigInt&)': user.cpp:12: warning: comparison between signed and unsigned integer expressions user.cpp: In member function 'BigInt& BigInt::operator=(long long int)': user.cpp:23: warning: no return statement in function returning non-void user.cpp: In member function 'BigInt& BigInt::operator+=(const BigInt&)': user.cpp:34: warning: comparison between signed and unsigned integer expressions user.cpp:44: warning: comparison between signed and unsigned integer expressions user.cpp:42: warning: unused variable 'k' user.cpp: In member function 'BigInt& BigInt::operator+=(long long int)': user.cpp:64: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'int main()': user.cpp:85: warning: unused variable 'k' user.cpp: In member function 'BigInt& BigInt::operator=(long long int)': user.cpp:23: warning: control reaches end of non-void function user.cpp: In member function 'BigInt& BigInt::operator+=(long long int)': user.cpp:69: warning: control reaches end of non-void function user.cpp: In member function 'BigInt& BigInt::operator+=(const BigInt&)': user.cpp:55: warning: control reaches end of non-void function