Duplicate entry while reading from ifstream into vector

Hi,
I'm new at C++, I'm using Stroustrup's book to learn and trying to
finish an exercise on page 505 (#3) and it works except that I am
getting an duplicate string read into a vector and can't figure out
the reason. This is not a homework assignment, I want to learn C++ as
a skill:

#include <fstream>
using std::fstream;
using std::ifstream;
using std::ofstream;

#include <iostream>
using std::cout;
using std::endl;
using std::getline;
using std::ios;

#include <string>
using std::string;

#include <vector>
using std::vector;

int main( int argc, char *argv[] )
{
        if(argc != 2) {
                cout << "Incorrect number of arguments, should be two,
turkey." << endl;
                exit(1);
        }

        ifstream readFile( argv[1], ios::in );
        cout << "argv[1] is " << argv[1] << endl << endl;
        if( !readFile) {
                cout << "Can't open " << argv[1] << ", exiting." <<
endl;
                return 0;
        }
        else
                cout << argv[1] << " opened for reading." << endl <<
endl;

        string temp;
        vector< string > lw;
        //while( readFile && !readFile.eof() ) {
        while( !readFile.fail() ) {
                readFile >> temp;
                cout << "temp is: " << temp << endl;
                lw.push_back(temp);
        }
        readFile.close();
        cout << endl;
        cout << "Here's the vector." << endl;

        for( vector<string>::iterator p = lw.begin(); p != lw.end(); +
+p)
                cout << *p << endl;

        return 0;
}

When I execute the program, no matter which text file I use, the last
word in the file is duplicated (there's not a duplicated string at the
end of the file), such as if the last word is "dawn," it appears twice
when I output the strings in the while loop and also with the
iterator.

I've tried changing the while loop to use different tests to determine
the end of the file but I get a duplicate line each time.

When the end of file is reached, the while loop should terminate and
not call push_back() again but for some reason, it calls it twice.

I've tried to use an istringstream as well but always end up with the
last word in the file duplicated.

I apologize ahead of time if this is a basic issue but I can't
eliminate the duplicate entry.

Steve