pr05016.cpp

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////////////////////////////////////////
// File Name: pr05016.cpp
////////////////////////////////////////
#include <iostream>

// Declare the Holder structure.
union Holder
{
    char holdchar;
    short int holdint;
    long int holdlong;
    float holdfloat;
};

// Function prototype.
void DisplayHolder(Holder, char*);

////////////////////////////////////////
// The main() function.
////////////////////////////////////////
int main()
{
    Holder hld;

    // Assign to first member.
    hld.holdchar = 'X';
    DisplayHolder(hld, "char");

    // Assign to second member.
    hld.holdint = 12345;
    DisplayHolder(hld, "int");

    // Assign to third member.
    hld.holdlong = 7654321;
    DisplayHolder(hld, "long");

    // Assign to fourth member.
    hld.holdfloat = 1.23;
    DisplayHolder(hld, "float");

    return 0;
}

////////////////////////////////////////
// Display the current value of the
// Holder union.
////////////////////////////////////////
void DisplayHolder(Holder hld, char* tag)
{
    std::cout << "---Initialized " << tag << " ---"
              << std::endl;
    std::cout << "holdchar  "  << hld.holdchar  << std::endl;
    std::cout << "holdint   "  << hld.holdint   << std::endl;
    std::cout << "holdlong  "  << hld.holdlong  << std::endl;
    std::cout << "holdfloat  " << hld.holdfloat << std::endl;
}