Compilare: main.cpp: In function 'void DFS(int, bool)': main.cpp:60:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < F[nr].size(); ++i ) ~~^~~~~~~~~~~~~~ main.cpp: In function 'void Do()': main.cpp:109:6: warning: 'start_side' may be used uninitialized in this function [-Wmaybe-uninitialized] DFS( start, start_side ); ~~~^~~~~~~~~~~~~~~~~~~~~ main.cpp:109:27: warning: 'start' may be used uninitialized in this function [-Wmaybe-uninitialized] DFS( start, start_side ); ^