c++ - symbol endl and cout could not be resolved -

i have written code book reading complier warns symbol cout , endl not resolved. why that.

#include <iostream> #include <float.h>  int main()  {     cout << "float: " << endl          << "stevilo decimalnih mest: " << flt_dig         << endl          << "natancnost stevila....: " << flt_epsilon      << endl          << "najmanjse stevilo.....: " << flt_min          << endl          << "najvecje stevilo......: "  << flt_max         << endl          << "bitov v mantisi.......: "  << flt_mant_dig    << endl          << "najvecji eksponent....: "  << flt_max_10_exp  << endl          << "najmlajsi eksponent...: "  << flt_min_10_exp  << endl;      return 0; } 

you have use namespace:

#include <iostream> #include <float.h> using namespace std; 

or:

std::cout 

you can read more namespaces in c++ here