Compilare: main.cpp: In member function 'void BigNumber::shift_right(int)': main.cpp:91:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 91 | if (power >= digits.size()) { | ~~~~~~^~~~~~~~~~~~~~~~ main.cpp: In constructor 'BigNumber::BigNumber(const std::string&)': main.cpp:116:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 116 | for (int i = 0; i < digits.size(); ++i) { | ~~^~~~~~~~~~~~~~~ main.cpp: In member function 'long long int BigNumber::to_llong()': main.cpp:171:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 171 | for (int i = 0; i < digits.size(); ++i) { | ~~^~~~~~~~~~~~~~~ main.cpp: In function 'std::istream& operator>>(std::istream&, BigNumber&)': main.cpp:184:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 184 | for (int i = 0; i < other.digits.size(); ++i) { | ~~^~~~~~~~~~~~~~~~~~~~~