#include <iostream>

using namespace std;

void print(int* p);
void swap(int& a, int& b);

int main()
{
    int a[] = {2,11,3,5,7};
    print(a);
    swap(a[1],a[4]);
    swap(a[1],a[2]);
    swap(a[2],a[3]);
    print(a);
}

void print(int* p)
{
    for (int i = 0; i < 5; i++)
        cout << p[i] << "   ";
    cout << endl;
}

void swap(int& a, int& b)
{
    cout << "a=" << a << "  b=" << b << endl;
    int temp;
    temp = a;
    a = b;
    b = temp;
    cout << "a=" << a << "  b=" << b << endl;
}