Compilare: main.cpp: In function 'int main()': main.cpp:25:30: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 25 | if(arr[i].size() > nmax){ | ~~~~~~~~~~~~~~^~~~~~ main.cpp:34:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 34 | for(int k = 0; k < arr[i].size(); k++){ | ~~^~~~~~~~~~~~~~~ main.cpp:48:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 48 | if(c == arr[i].size()){ | ~~^~~~~~~~~~~~~~~~