intvec.cc

C++作业

# include <iostream>
# include "IntVec.hh"  

// ******************************************************************
// CONSTRUCTORS

IntVec::IntVec() {
    // Default Constructor
}

// ******************************************************************
// ACCESSORS


// ******************************************************************
// METHODS

void IntVec::test() {
    cerr << "NOTE: Testing IntVec" << endl;
}

// ******************************************************************
// CODE FOR NESTED CLASS 'iterator'
// ******************************************************************

IntVec::iterator::iterator(IntVec* vec, int position) {
    // NOTE: The header file provides default arguments
    // for both 'vec' (NULL) and 'position' (0).  However,
    // when defining the method, you do NOT provide the
    // default values).
    this->setContainer(vec);
    this->setPosition(position);
}

IntVec::iterator::iterator(IntVec::iterator& it) {
    // Why aren't we passing 'it' as a 'const iterator&' here?
    // Can you find a way to solve this problem?
    this->setContainer( it.container() );
    this->setPosition( it.getPosition() );
}

IntVec::iterator& IntVec::iterator::operator++() {
    // We increment our current position by one.
    // If the result is beyond the range of the
    // underlying vector (or if the position is already
    // marking the "end"), we set the position to
    // the special value -1.

    // Uncomment this when you get 'size' working on IntVec
    /*
    int pos = this->getPosition();
    if ( pos >= 0 ) {
	++pos;
	unsigned sz  = this->getContainer()->size();
	if ( ((unsigned)pos) < sz ) {
	    this->setPosition(pos);
	} else {
	    this->setPosition(-1);
	}
    }
    */
    return *this;
}

int& IntVec::iterator::operator*() {
    // FIX THIS CODE!  This is NOT safe code.  Why it is
    // unsafe is left as an exercise.

    #ifdef WORKING
    // Remove the 'ifdef' when you get operator[] working in IntVec
    // (or use some other method to gain access to an element
    // of the IntVec container
    IntVec* container = this->container();
    return (*container)[this->getPosition()];
    # else
    // This is just a temporary hack until you get the preceeding code working.
    // You should determine why I am doing this.  Why have any code
    // here at all?  Why use a static variable?  Remember that this
    // is just a hack, it isn't actually doing what it is supposed to.
    static int i = 0;
    return i;
    # endif // not WORKING
}

bool IntVec::iterator::operator!=(const iterator& it) const {
    return ((this->getPosition() == it.getPosition()) &&
	    (this->getContainer() == it.getContainer())) ? false : true;
}