function returning two values

/* C++ Primer - 4/e
 *
 * 1st example from section 7.2.2, page 234
 * returning 2 values from a function
 *
 * STATEMENT:
 * to find a specific value in a vector and number of times
 * that value occurs in th vector.
 */

#include <iostream>
#include <vector>

/* returns an iterator that refers to the first occurence of
"find_this_value"
the reference paramater "occurs" contains a second return value, the
number of times "find_this_value" occured in the vector
*/
std::vector<int>::const_iterator find_val(
       std::vector<int>::const_iterator beg,
       std::vector<int>::const_iterator end,
       int find_this_value,
       std::vector<int>::size_type& occurs)
{
  /* res_iter will hold the first occurence, if any */
  std::vector<int>::const_iterator res_iter = end;
  occurs = 0;

  for( ; beg != end; ++beg)
    {
      if ( *beg == find_this_value )
    {
      if ( res_iter == end ) /* this will remeber the 1st occurence */
        {
          res_iter = beg;
        }
      ++occurs;
    }
    }

  return res_iter;
}

int main()
{
  std::cout << "enter some numbers to creat a vector : ";
  std::vector<int> ivec;
  int i;
  while(std::cin >> i)
    {
      ivec.push_back(i);
    }

  /* clear the input stream */
  std::cin.clear();
  std::cout << "which numbe you want to find: ";
  int find_value;
  std::cin >> find_value;

  std::vector<int>::const_iterator begin = ivec.begin();
  std::vector<int>::const_iterator end = ivec.end();

  find_val(begin, end, find_value);

  return 0;
}

as expected this function never compiles because function call expects
the 4 arguments whereas 3 are given. but how i am supposed to provide
4th argument when what i want to find out is the 4th argument and the
author says that 4th argument is the 2nd return value. i am confused
on this

(BTW, it seems like circular-dependencies problem of emerge)