Compilare: user.cpp: In function ‘bool relabel(int, flow_graph&, std::vector<int>&, std::vector<int>&)’: user.cpp:23:56: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (x[nod] > 0 && l[nod] <= min && min != r.size () + 1) { ^ user.cpp: In function ‘int max_flow(graph&, int, int)’: user.cpp:48:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < g.size (); i++) { ^ user.cpp:67:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < r.size(); i++) { ^