Compilare: user.cpp: In function ‘int main()’: user.cpp:71:23: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘long int’ [-Wformat=] fprintf(g, "%d\n", nr); ^ user.cpp:72:45: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘__gnu_cxx::__alloc_traits<std::allocator<long int> >::value_type {aka long int}’ [-Wformat=] for (i=0; i<nr; i++) fprintf(g, "%d ", c[i]); ^