C++における4種類の数値交換方法

#include 

using namespace std;

void Swap1(int &a, int &b)
{
    int c = a;
    a = b;
    b = c;
}

void Swap2(int& a, int& b)
{
    a = a ^ b;
    b = a ^ b;
    a = a ^ b;
}

template  
void Swap3(T &a, T& b)
{
    T c(a);
    a = b;
    b = c;
}

void Swap4(int* a, int* b)  //C  
{
    int c = *a;
    *a = *b;
    *b = c;
}

int main()
{
    int i=0;
    int j=1;

    cout << "i = " << i << "j = " << j << endl;

    Swap4(&i, &j);

    cout << "i = " << i << "j = " << j << endl;

    return 0;
}