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B'day paradox problem

Birthday paradox problem is to fill a room with n people and get the probability of at least 2 people having the same b'day. This is given for 25 people as 1-(364.363.362....341)/(365^24). This can be done using the following snippet in C++.
http://en.wikipedia.org/wiki/Birthday_problem#Calculating_the_probability

void bDayParadox() {

    float result = 1.0;
    int numerator = 364.0;
    for (int i = 0; i < 24; i++) {
        result = result * (numerator / 365.0);       
        numerator = numerator - 1.0;
    }

    std::cout << 1.0-result << std::endl;

}

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