fork download 
  1. // twoswap.cpp -- specialization overrides a template
  2. #include <iostream>
  3. template <typename T>
  4. void Swap(T &a, T &b);
  5.  
  6. struct job
  7. {
  8.     char name[40];
  9.     double salary;
  10.     int floor;
  11. };
  12.  
  13. // explicit specialization
  14. template <> void Swap<job>(job &j1, job &j2);
  15. void Show(job &j);
  16.  
  17. int main()
  18. {
  19.     using namespace std;
  20.     cout.precision(2);
  21.     cout.setf(ios::fixed, ios::floatfield);
  22.     int i = 10, j = 20;
  23.     cout << "i, j = " << i << ", " << j << ".\n";
  24.     cout << "Using compiler-generated int swapper:\n";
  25.     Swap(i,j);    // generates void Swap(int &, int &)
  26.     cout << "Now i, j = " << i << ", " << j << ".\n";
  27.  
  28.     job sue = {"Susan Yaffee", 73000.60, 7};
  29.     job sidney = {"Sidney Taffee", 78060.72, 9};
  30.     cout << "Before job swapping:\n";
  31.     Show(sue);
  32.     Show(sidney);
  33.     Swap(sue, sidney); // uses void Swap(job &, job &)
  34.     cout << "After job swapping:\n";
  35.     Show(sue);
  36.     Show(sidney);
  37.     // cin.get();
  38.     return 0;
  39. }
  40.  
  41. template <typename T>
  42. void Swap(T &a, T &b)    // general version
  43. {
  44.     T temp;
  45.     temp = a;
  46.     a = b;
  47.     b = temp;
  48. }
  49.  
  50. // swaps just the salary and floor fields of a job structure
  51.  
  52. template <> void Swap<job>(job &j1, job &j2)  // specialization
  53. {
  54.     double t1;
  55.     int t2;
  56.     t1 = j1.salary;
  57.     j1.salary = j2.salary;
  58.     j2.salary = t1;
  59.     t2 = j1.floor;
  60.     j1.floor = j2.floor;
  61.     j2.floor = t2;
  62. }
  63.  
  64. void Show(job &j)
  65. {
  66.     using namespace std;
  67.     cout << j.name << ": $" << j.salary
  68.          << " on floor " << j.floor << endl;
  69. }
  70.  
Success #stdin #stdout 0s 4900KB
comments (?)
stdin 
Standard input is empty
stdout 
i, j = 10, 20.
Using compiler-generated int swapper:
Now i, j = 20, 10.
Before job swapping:
Susan Yaffee: $73000.60 on floor 7
Sidney Taffee: $78060.72 on floor 9
After job swapping:
Susan Yaffee: $78060.72 on floor 9
Sidney Taffee: $73000.60 on floor 7
https://ideone.com/RuJhux
language:
C++ (gcc 8.3)
created:
4 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!