distanta.cpp: In constructor 'InputReader::InputReader(const char*)': distanta.cpp:25: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result distanta.cpp: In constructor 'InputReader::InputReader(const char*)': distanta.cpp:25: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result distanta.cpp: In constructor 'InputReader::InputReader(const char*)': distanta.cpp:25: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result distanta.cpp: In member function 'void InputReader::advance()': distanta.cpp:52: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result distanta.cpp: In function 'void det_ans(int)': distanta.cpp:71: warning: unused variable 'j' distanta.cpp: In function 'void write()': distanta.cpp:115: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result