Compilare: main.cpp: In function 'int paranteze(std::__cxx11::string)': main.cpp:7:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<s.size();i++) ~^~~~~~~~~ main.cpp:13:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=i+1;j<s.size();j++) ~^~~~~~~~~