[user02@FC4 Lesson11]$ cat -n nochange.cpp

   1  #include <iostream>
   2  using namespace std;
   3
   4  void display_values(int a, int b)

   5  {
   6     a = 1001;
   7     b = 1001;
   8
   9     cout << "The values within display_values are " <<  a << " and " << b << endl;
  10  }
  11
  12  int main()
  13  {
  14     int big = 2002, small = 0;
  15
  16     cout << "Values before function " << big << " and " << small << endl;
  17
  18     display_values(big, small);
  19
  20     cout << "Values after function " << big << " and " << small << endl;
  21
  22     return 0;
  23  }

[user02@FC4 Lesson11]$ g++ -o nochange nochange.cpp
[user02@FC4 Lesson11]$ ./nochange
Values before function 2002 and 0
The values within display_values are 1001 and 1001
Values after function 2002 and 0
[user02@FC4 Lesson11]$