Compilare: user.cpp: In function ‘void DFS(const int&)’: user.cpp:39:31: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] if(v[p -> data.first] == 0 & middle <= p -> data.second) ^ user.cpp: In member function ‘char InParser::read_ch()’: user.cpp:71:38: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^