Compilare: user.cpp: In member function ‘void santa::init()’: user.cpp:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In member function ‘void santa::dfs(int)’: user.cpp:48: warning: comparison between signed and unsigned integer expressions user.cpp: In member function ‘void santa::show()’: user.cpp:89: warning: comparison between signed and unsigned integer expressions