Compilare: user.cpp: In function ‘void read(int&)’: user.cpp:20:36: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(ch,1,bsize,stdin); ^ user.cpp:38:36: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(ch,1,bsize,stdin); ^ user.cpp:46:36: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(ch,1,bsize,stdin); ^ user.cpp: In function ‘int main()’: user.cpp:60:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ciclueuler.in","r",stdin); ^ user.cpp:61:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ciclueuler.out","w",stdout); ^ user.cpp:62:29: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread (ch,bsize,1,stdin); ^