Compilare: main.cpp: In constructor 'Big::Big(std::string)': main.cpp:48:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp: In static member function 'static void Big::_sub_(std::vector<int>&, const std::vector<int>&)': main.cpp:161:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp:163:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp: In static member function 'static void Big::_sub2_(std::vector<int>&, const std::vector<int>&)': main.cpp:176:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp:177:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp:178:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp: In static member function 'static void Big::_add_(std::vector<int>&, const std::vector<int>&)': main.cpp:191:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp:193:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp: In static member function 'static std::vector<int> Big::_slow_mult_(const std::vector<int>&, const std::vector<int>&)': main.cpp:226:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp:227:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp:234:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp: In static member function 'static std::pair<std::vector<int>, std::vector<int> > Big::_div_(std::vector<int>, std::vector<int>)': main.cpp:280:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] main.cpp: In function 'void solve()': main.cpp:343:16: warning: unused variable 's' [-Wunused-variable]