Compilare: In file included from /usr/include/c++/4.8/cassert:43:0, from user.cpp:9: user.cpp: In function ‘int vertex_dijkstra(int, int, const std::vector<std::vector<int> >&, const std::vector<int>&, const std::vector<bool>&)’: user.cpp:22:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(cost.size() == n); ^ user.cpp:23:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(forbidden.size() == n); ^