Compilare: user.cpp: In function ‘int main()’: user.cpp:69:17: warning: unused variable ‘l’ [-Wunused-variable] int NR = 0, l = 0; ^ user.cpp:67:44: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("expectedpos.out", "w", stdout); ^ user.cpp: In member function ‘char InParser::read_ch()’: user.cpp:16:38: 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); ^