Compilare: main.cpp: In function 'int check(std::string, std::string)': main.cpp:18:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 18 | for (i = 0; i < a.size() and i < b.size(); i++) | ~~^~~~~~~~~~ main.cpp:18:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 18 | for (i = 0; i < a.size() and i < b.size(); i++) | ~~^~~~~~~~~~ main.cpp: In function 'long long int aoleu(std::string, std::string)': main.cpp:33:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 33 | for (i = 0; i < a.size(); i++) | ~~^~~~~~~~~~ main.cpp: In function 'long long int adun(long long int, long long int)': main.cpp:71:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 71 | for (i = 1; i <= a1.size() + 1; i++) | ~~^~~~~~~~~~~~~~~~ main.cpp:85:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 85 | for (i = 1; i <= b1.size(); i++) | ~~^~~~~~~~~~~~