Compilare: user.cpp: In function ‘void read()’: user.cpp:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int BFS()’: user.cpp:100: warning: suggest explicit braces to avoid ambiguous ‘else’