Compilare: user.cpp: In function ‘void CreateDiam(std::vector<int>*, int)’: user.cpp:164:9: warning: variable ‘a’ set but not used [-Wunused-but-set-variable] int a; ^ user.cpp: In function ‘std::pair<int, int> FindRts(std::vector<int>*)’: user.cpp:202:9: warning: variable ‘a’ set but not used [-Wunused-but-set-variable] int a; ^ user.cpp: In function ‘bool Isomorph(std::vector<int>*, std::vector<int>*)’: user.cpp:261:9: warning: variable ‘a’ set but not used [-Wunused-but-set-variable] int a; ^ user.cpp:284:9: warning: variable ‘a’ set but not used [-Wunused-but-set-variable] int a; ^ user.cpp: In member function ‘void InputReader::advance()’: user.cpp:41:41: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, SIZE, 1, input_file); ^ user.cpp: In constructor ‘InputReader::InputReader(const char*)’: user.cpp:19:39: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, SIZE, 1, input_file); ^