Compilare: user.cpp: In function ‘void solve()’: user.cpp:61:9: warning: unused variable ‘now’ [-Wunused-variable] int now = n; ^ user.cpp:63:9: warning: variable ‘first’ set but not used [-Wunused-but-set-variable] int first, second = 0; ^ user.cpp:63:16: warning: unused variable ‘second’ [-Wunused-variable] int first, second = 0; ^ user.cpp: In constructor ‘InputReader::InputReader(const char*)’: user.cpp:10:47: 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 member function ‘void InputReader::advance()’: user.cpp:32:51: 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); ^