Compilare: user.cpp: In function ‘double dijkstra(int, int)’: user.cpp:102:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<G[x].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:142:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j=0; j<D[i].size(); ++j) ^ user.cpp:148:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (j!=D[i].size()-1) ^ user.cpp:161:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k=0; k<D[i].size(); ++k) ^