What will be the output of the following C++ code?

#include <iostream>
#include <iterator>
using namespace std;
int main ()
{
    try {
        double value1, value2;
        istream_iterator<double> eos;       
        istream_iterator<double> iit (cin);   
        if (iit != eos) 
            value1 = *iit;
        iit++;
        if (iit != eos) 
            value2 = *iit;
        cout << (value1 * value2) << endl;
    }
    catch (...) {
        cout << "Unknown exception: " << endl;
    }
    return 0;
}