Compilare: user.cpp: In function ‘int main()’: user.cpp:76:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0; j < V[i].size(); ++ j) ^ user.cpp:82:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0; j < Q[i].size(); ++ j) ^ user.cpp:99:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0; j < V[i].size(); ++ j) ^ user.cpp:105:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0; j < Q[i].size(); ++ j) ^