Compilare: user.cpp: In function ‘void nivel()’: user.cpp:73:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<niv[nivmax].size(); ++j) ^ user.cpp:76:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(k=0; k<L[vf].size(); ++k) ^ user.cpp:45:9: warning: unused variable ‘i’ [-Wunused-variable] int i, j, k, total=1, vf; ^ user.cpp: In function ‘void pd()’: user.cpp:95:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<niv[i].size(); ++j) ^