Answers for "what are templates in c++"

template in c++

template <typename T>
void Swap(T &n1, T &n2)
{
	T temp;
	temp = n1;
	n1 = n2;
	n2 = temp;
}

template in c++

// template function
template <class T>
T Large(T n1, T n2)
{
	return (n1 > n2) ? n1 : n2;
}

what is template in c++

A template is a simple and yet very powerful tool in C++. The simple idea is to pass data type as a parameter so that we don’t need to write the same code for different data types. For example, a software company may need sort() for different data types. Rather than writing and maintaining the multiple codes, we can write one sort() and pass data type as a parameter. 
C++ adds two new keywords to support templates: ‘template’ and ‘typename’. The second keyword can always be replaced by keyword ‘class’.

templates c++

template  < typename  T > 
inline  T  max ( T  a ,  T  b )  { 
    return  a  >  b  ?  a  :  b ; 
}

int  main () 
{ 
    // Isso chamará max <int> por dedução implícita do argumento. 
    std :: cout  <<  max ( 3 ,  7 )  <<  std :: endl ;

    // Isso chamará max <double> por dedução implícita do argumento. 
    std :: cout  <<  max ( 3.0 ,  7.0 )  <<  std :: endl ;

    // Isso depende do compilador. Alguns compiladores lidam com isso definindo uma 
    função de 
    modelo // como double max <double> (double a, double b) ;, enquanto em alguns compiladores // precisamos convertê-lo explicitamente, como std :: cout << max <double> (3,7,0); 
    std :: cout  <<  max ( 3 ,  7.0 )  <<  std :: endl ; 
    std :: cout  <<  max < double > ( 3 ,  7.0 )  <<  std :: endl ; 
    return  0 ; 
}

c++ template

// class templates
#include <iostream>
using namespace std;

template <class T>
class mypair {
    T a, b;
  public:
    mypair (T first, T second)
      {a=first; b=second;}
    T getmax ();
};

template <class T>
T mypair<T>::getmax ()
{
  T retval;
  retval = a>b? a : b;
  return retval;
}

int main () {
  mypair <int> myobject (100, 75);
  cout << myobject.getmax();
  return 0;
}

c++ template

#include <bits/stdc++.h>
using namespace std;
template <class T>
class Vector{
    public:
        T *arr;
        T size;

        Vector(int size){
            this->size = size;
            arr = new T[size];
        }
        T dotProduct(Vector &v){
            T d = 0;
            for(int i = 0; i<size; i++){
                d += this->arr[i] * v.arr[i];
            }
            return d;
        }
};
int main(){
    Vector<int> v1(3);
    v1.arr[0] = 1;
    v1.arr[1] = 2;
    v1.arr[2] = 3;
    Vector<int> v2(3);
    v2.arr[0] = 4;
    v2.arr[1] = 5;
    v2.arr[2] = 6;
    int a = v1.dotProduct(v2);
    cout<<a<<endl;
    Vector<float> v3(3);
    v3.arr[2] = 3.2;
    v3.arr[0] = 1.2;
    v3.arr[1] = 2.2;
    Vector<float> v4(3);
    v4.arr[0] = 4.4;
    v4.arr[1] = 5.4;
    v4.arr[2] = 6.4;
    float a1 = v3.dotProduct(v4);
    cout<<a1<<endl;

    return 0;
}