Compilare: user.cpp: In function 'void DFS(int)': user.cpp:98: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'int DFST(int)': user.cpp:111: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'void face_graf()': user.cpp:145: warning: comparison between signed and unsigned integer expressions user.cpp:146: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'void sort_topologic()': user.cpp:163: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'void atribuire_valori()': user.cpp:178: warning: comparison between signed and unsigned integer expressions