Compilare: user.cpp: In function ‘void read(int&)’: user.cpp:48:67: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if(cursor==Bsize) fread(Buffer, 1, Bsize, stdin), cursor=0; ^ user.cpp:55:67: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if(cursor==Bsize) fread(Buffer, 1, Bsize, stdin), cursor=0; ^ user.cpp: In function ‘int main()’: user.cpp:76:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arb.in", "r", stdin); ^ user.cpp:77:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arb.out", "w", stdout); ^ user.cpp:79:45: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buffer, 1, Bsize, stdin), cursor=0; ^