Compilare: main.cpp: In function 'void add(node*, std::__cxx11::string, int)': main.cpp:18:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i==word.size()){ ~^~~~~~~~~~~~~ main.cpp:25:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<current->next.size() && !found){ ~^~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'void del(node*, std::__cxx11::string, int)': main.cpp:39:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i==word.size()){ ~^~~~~~~~~~~~~ main.cpp:47:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<current->next.size() && !found){ ~^~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'void aparitii(std::__cxx11::string, node*, int)': main.cpp:58:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i==word.size()){ ~^~~~~~~~~~~~~ main.cpp:66:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<current->next.size() && !found){ ~^~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'void prefix(std::__cxx11::string, node*, int)': main.cpp:79:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i==word.size()){ ~^~~~~~~~~~~~~ main.cpp:87:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<current->next.size() && !found){ ~^~~~~~~~~~~~~~~~~~~~~