Compilare: main.cpp: In function 'void solve()': main.cpp:31:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 31 | for(int i = 0; i <= s.length(); ++i) | ~~^~~~~~~~~~~~~ main.cpp:42:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 42 | while(i < s.length()) | ~~^~~~~~~~~~~~