Compilare: main.cpp: In member function 'int& FIB::operator[](int)': main.cpp:28:5: warning: control reaches end of non-void function [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:42:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("fibsum.in","r",stdin); ^ main.cpp:43:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("fibsum.out","w",stdout); ^