Compilare: main.cpp: In function 'void add(nod*, std::__cxx11::string, int)': main.cpp:22:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz==s.size()){ ~~~^~~~~~~~~~ main.cpp: In function 'void rem(nod*, std::__cxx11::string, int)': main.cpp:31:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz==s.size()){ ~~~^~~~~~~~~~ main.cpp: In function 'int query(nod*, std::__cxx11::string, int)': main.cpp:42:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz==s.size())return n->apar; ~~~^~~~~~~~~~ main.cpp:44:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz!=s.size())return query(n->urm[s[poz]-'a'],s,poz+1); ~~~^~~~~~~~~~ main.cpp: In function 'int query_pref(nod*, std::__cxx11::string, int)': main.cpp:48:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz==s.size())return poz; ~~~^~~~~~~~~~ main.cpp:50:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz!=s.size())return query_pref(n->urm[s[poz]-'a'],s,poz+1); ~~~^~~~~~~~~~ main.cpp: In function 'int query(nod*, std::__cxx11::string, int)': main.cpp:45:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ main.cpp: In function 'int query_pref(nod*, std::__cxx11::string, int)': main.cpp:51:1: warning: control reaches end of non-void function [-Wreturn-type] } ^