Compilare: user.cpp: In function ‘void addedge(int, int, int)’: user.cpp:56:33: warning: narrowing conversion of ‘(g[j].std::vector<_Tp, _Alloc>::size<Edge, std::allocator<Edge> >() + ((std::vector<Edge>::size_type)loop))’ from ‘std::vector<Edge>::size_type {aka unsigned int}’ to ‘int’ inside { } [-Wnarrowing] Edge direct = {j, g[j].size() + loop, false, false, ind}; ^ user.cpp:57:32: warning: narrowing conversion of ‘g[i].std::vector<_Tp, _Alloc>::size<Edge, std::allocator<Edge> >()’ from ‘std::vector<Edge>::size_type {aka unsigned int}’ to ‘int’ inside { } [-Wnarrowing] Edge inverse = {i, g[i].size(), false, true, ind}; ^ user.cpp: In function ‘void bfs()’: user.cpp:72:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < g[from].size(); i++){ ^ In file included from /usr/include/c++/4.8/cassert:43:0, from user.cpp:3: user.cpp: In function ‘int main()’: user.cpp:143:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(esol.size() == n); ^