Compilare: main.cpp: In function 'void construct(std::__cxx11::string, std::__cxx11::string)': main.cpp:32:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(ind<=s.size()-1 and s[ind-1]==',') ~~~^~~~~~~~~~~~ main.cpp:43:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(ind<=s.size()-1 and s[ind-1]==',') ~~~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:54:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<sol.size();++i) ~^~~~~~~~~~~