pr06029.cpp

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////////////////////////////////////////
// File Name: pr06029.cpp
////////////////////////////////////////
#include <iostream>

// A big structure.
struct bigone
{
    int serno;
    char text[1000];
};

// Two function prototypes with a structure parameter.
void slowfunc(bigone p1);    // Call by value.
void fastfunc(bigone& p1);   // Call by reference.

////////////////////////////////////////
// The main() function.
////////////////////////////////////////
int main()
{
    static bigone bo = {123, "This is a BIG structure"};

    // This call will take a while.
    slowfunc(bo);

    // This call will be faster than the previous one.
    fastfunc(bo);

    return 0;
}

////////////////////////////////////////
// A call-by-value function.
////////////////////////////////////////
void slowfunc(bigone p1)
{
    std::cout << p1.serno << std::endl;
    std::cout << p1.text << std::endl;
}

////////////////////////////////////////
// A call by reference function.
////////////////////////////////////////
void fastfunc(bigone& p1)
{
    std::cout << p1.serno << std::endl;
    std::cout << p1.text << std::endl;
}