C++ Tutorial/template/overload template function

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Overload generic method and non-generic method

#include<iostream.h>
#include<string.h>
template<class T>
T min(T a,T b)
{
    cout << "generic";
       return (a<b?a:b);
}
char *min(char *a,char *b)
{
    cout << "not generic";
       return (strcmp(a,b)<0?a:b);
}
int main()
{
  double a=3.56,b=8.23;
  char s1[]="Hello",s2[]="Good";
  cout<<min(a,b)<<endl;
  cout<<min(s1,s2)<<endl;
}
generic3.56
not genericGood

Using an overloaded function template

#include <iostream>
using std::cout;
using std::endl;
template<class T> T larger(T a, T b);
long* larger(long* a, long* b);
template <class T> T larger (const T array[], int count); // Overloaded templat
e prototype
int main() {
  cout << "Larger of 1.5 and 2.5 is " << larger(1.5, 2.5) << endl;
  cout << "Larger of 3.5 and 4.5 is " << larger(3.5, 4.5) << endl;
 
  int a_int = 35;
  int b_int = 45;
  cout << larger(a_int, b_int)<< endl;
  
  long a_long = 9;
  long b_long = 8;
  cout << larger(a_long, b_long)<< endl;
  cout << *larger(&a_long,&b_long)<< endl;
  double x[] = { 10.5, 12.5, 2.5, 13.5, 5.5 };
  cout << larger(x, sizeof x/sizeof x[0]) << endl;
return 0;
}
template <class T> T larger(T a, T b) {
  cout << "standard version " << endl;
  return a>b ? a : b;
}
long* larger(long* a, long* b) {
  cout << "overloaded version for long* " << endl;
  return *a>*b ? a : b;
}
template <class T> T larger (const T array[], int count) {
  cout << "template overload version for arrays " << endl;
  T result = array[0];
  for(int i = 1 ; i < count ; i++)
    if(array[i] > result)
      result = array[i];
  return result;
}
standard version
Larger of 1.5 and 2.5 is 2.5
standard version
Larger of 3.5 and 4.5 is 4.5
standard version
45
standard version
9
overloaded version for long*
9
template overload version for arrays
13.5

Using function template specialization

#include <iostream>
using std::cout;
using std::endl;
template<class T> T larger(T a, T b);             // Function template prototyp
e
template<> long* larger<long*>(long* a, long* b); // Specialization
int main() {
  cout << "Larger of 1.5 and 2.5 is " << larger(1.5, 2.5) << endl;
  cout << "Larger of 3.5 and 4.5 is " << larger(3.5, 4.5) << endl;
 
  int a_int = 35;
  int b_int = 45;
  cout << larger(a_int, b_int)<< endl;
 
  long a_long = 9;
  long b_long = 8;
  cout << larger(a_long, b_long)<< endl;
  cout << *larger(&a_long,&b_long)<< endl;
return 0;
}
template <class T> T larger(T a, T b) {
  cout << "standard version " << endl;
  return a>b ? a : b;
}
template <> long* larger<long*>(long* a, long* b) {
  cout << "specialized version " << endl;
  return *a>*b ? a : b;
}
standard version
Larger of 1.5 and 2.5 is 2.5
standard version
Larger of 3.5 and 4.5 is 4.5
standard version
45
standard version
9
specialized version
9