Compilare: user.cpp: In function ‘void read()’: user.cpp:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int BFS()’: user.cpp:96: warning: suggest explicit braces to avoid ambiguous ‘else’