Compilare: user.cpp: In function ‘int main()’: user.cpp:64:62: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(sir[j] >= '0' && sir[j] <= '9' && j < sir.size()) ^ user.cpp:73:62: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(sir[j] >= '0' && sir[j] <= '9' && j < sir.size()) ^ user.cpp:82:62: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(sir[j] >= '0' && sir[j] <= '9' && j < sir.size()) ^ user.cpp:107:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < v[nod].size(); i++) ^