Compilare: user.cpp: In function ‘int bfs(int)’: user.cpp:31:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < g[from].size(); i++) { ^ user.cpp: In function ‘int main()’: user.cpp:131:26: warning: ‘fs’ may be used uninitialized in this function [-Wmaybe-uninitialized] out << i << ' ' << reff << '\n'; ^