#include <iostream>

using namespace std;

void echange(char& a, char& b)
{
    char c;

    c = a;
    a = b;
    b = c;

    cout << "pendant la fonction a = " << a << endl;
    cout << "pendant la fonction b = " << b << endl;

    return;
}

void echangel(long& a, long& b)
{
    long c;

    c = a;
    a = b;
    b = c;

    cout << "pendant la fonction c = " << a << endl;
    cout << "pendant la fonction d = " << b << endl;

    return;
}

void echanged(double& a, double& b)
{
    double c;

    c = a;
    a = b;
    b = c;

    cout << "pendant la fonction e = " << a << endl;
    cout << "pendant la fonction f= " << b << endl << endl;

    return;
}

int main()
{
    char a;
    char b;
    long c = 1;
    long d = 5;
    double e = -1.2;
    double f = 3.1;

    cout << "a = " << a << endl;
    cout << "b = " << b << endl;
    cout << "c = " << c << endl;
    cout << "d = " << d << endl;
    cout << "e = " << e << endl;
    cout << "f = " << f << endl << endl;

    echange (a, b);
    echangel (c, d);
    echanged (e, f);

    cout << "apres la fonction a = " << a << endl;
    cout << "apres la fonction b = " << b << endl;
    cout << "apres la fonction c = " << c << endl;
    cout << "apres la fonction d = " << d << endl;
    cout << "apres la fonction e = " << e << endl;
    cout << "apres la fonction f = " << f << endl << endl;

    return 0;
}