Compilare: user.cpp: In function ‘int main()’: user.cpp:60:12: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] check[k] = NULL; ^ user.cpp:70:9: warning: unused variable ‘indexind’ [-Wunused-variable] int indexind = p->urm[ind]->_index; ^ user.cpp:71:9: warning: unused variable ‘indexopo’ [-Wunused-variable] int indexopo = p->urm[opo]->_index; ^ user.cpp:73:9: warning: unused variable ‘sizeind’ [-Wunused-variable] int sizeind = 0, sizeopo = 0; ^ user.cpp:73:22: warning: unused variable ‘sizeopo’ [-Wunused-variable] int sizeind = 0, sizeopo = 0; ^