Compilare: user.cpp: In function ‘int main()’: user.cpp:175:20: warning: unused variable ‘y’ [-Wunused-variable] int op, x, y; ^ user.cpp:166:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(infile, "r", stdin); ^ user.cpp: In function ‘void getInt(int&)’: user.cpp:45:39: 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, lim, stdin); ^ user.cpp:52:39: 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, lim, stdin); ^