Swap function.

[Theharpman]

Can someone explain to me, or even show me how to write a complete function that swaps the values of two specified array elements.Thank you.

[viliml]

the header "algorithm" has a function std::swap(a, b) wich swaps the values of a and b.
example:

#include <algorithm>
#include <iostream>

using namespace std;

int main()
{
     int array[]={1, 2};
     cout<<array[0]<<" "<<array[1]<<endl;
     swap(array[0], array[1]);
     cout<<array[0]<<" "<<array[1];
     return 0;
}

output:

1 2
2 1

[timmyyyyy]

You do it the same way you would to swap 2 values (for example, an int "array element" is considered the same as an int a;)

[z05DSL3A]

viliml,

While using std::swap is the way that you should swap elements in an array it dose not explain 'how to write a complete function that swaps the values' that the OP requested.

Theharpman,

A naive^* implementation of swap:

#include <iostream>

// a naive implementation of swap
void swap(int & a, int & b)
{
    int temp = a;
    a = b;
    b = temp;
}

// A template version of the above
template<typename T>
void swap(T &a, T &b)
{
    T t = a;
    a = b;
    b = t;
}

int main(void) 
{
    int an_array[] = {1, 2};
    
    std::cout << an_array[0] << " " << an_array[1] << std::endl;
    
    swap(an_array[0], an_array[1]);

    std::cout << an_array[0] << " " << an_array[1] << std::endl;

    // template version
    double a_double_array[] = {1.1, 2.2};

    std::cout << a_double_array[0] << " " << a_double_array[1] << std::endl;
    
    swap(a_double_array[0], a_double_array[1]);
    
    std::cout << a_double_array[0] << " " << a_double_array[1] << std::endl;
    
    return 0;
}

* By naive I just mean simple, straight forward version.