STL Algorithms Non Modifying Sequence Operations C++ Tutorial

#include         
#include 
#include 
#include 
#include 
using namespace std;
int main()
{
  cout << "Type some characters, including an 'x' followed\n"
    << "by at least one nonwhite-space character: " << flush;
  istream_iterator in(cin);
  istream_iterator eos;
  find(in, eos, 'x');
  cout << "The first nonwhite-space character following\n"
       << "the first 'x' was '" << *(++in) << "'." << endl;
  return 0;
}
Type some characters, including an 'x' followed
by at least one nonwhite-space character: x is after y
The first nonwhite-space character following
the first 'x' was 'i'.