Compilare: main.cpp: In member function 'void Dinic::add_edge(int, int, double)': main.cpp:30:42: warning: narrowing conversion of '(&((Dinic*)this)->Dinic::gr.std::vector<_Tp, _Alloc>::operator[]<std::vector<Edge>, std::allocator<std::vector<Edge> > >(((std::vector<std::vector<Edge> >::size_type)y)))->std::vector<_Tp, _Alloc>::size<Edge, std::allocator<Edge> >()' from 'std::vector<Edge>::size_type {aka long unsigned int}' to 'int' inside { } [-Wnarrowing] gr[x].pb ({y, 0, cap, gr[y].size ()}); ~~~~~~~~~~~^~ main.cpp:31:45: warning: narrowing conversion of '((&((Dinic*)this)->Dinic::gr.std::vector<_Tp, _Alloc>::operator[]<std::vector<Edge>, std::allocator<std::vector<Edge> > >(((std::vector<std::vector<Edge> >::size_type)x)))->std::vector<_Tp, _Alloc>::size<Edge, std::allocator<Edge> >() - 1ul)' from 'std::vector<Edge>::size_type {aka long unsigned int}' to 'int' inside { } [-Wnarrowing] gr[y].pb ({x, 0, cap, gr[x].size () - 1}); ~~~~~~~~~~~~~~^~~ main.cpp: In member function 'double Dinic::dfs(int, int, double)': main.cpp:54:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (start[node] < gr[node].size ()) { main.cpp: In member function 'double Dinic::maxflow()': main.cpp:73:49: warning: suggest parentheses around assignment used as truth value [-Wparentheses] while (flow = dfs (source, sink, INF)) ^ main.cpp: In function 'int main()': main.cpp:81:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("fear.in", "r", stdin); ^ main.cpp:82:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("fear.out", "w", stdout); ^