Compilare: main.cpp: In function 'std::string recursiv(int)': main.cpp:45:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 45 | if(poz>=s.size() || s[poz]==')' || s[poz]==']') | ~~~^~~~~~~~~~