class Easy286ReverseFactorial
{
    public static void main (String args[]) {
        Easy286ReverseFactorial easy = new Easy286ReverseFactorial();
        easy.reverseFactorial(3628800);
        easy.reverseFactorial(479001600);
        easy.reverseFactorial(6);
        easy.reverseFactorial(18);
    }
 
    public void reverseFactorial(int number) {
        int factorial=1 ,count = 1;
        while((factorial = (factorial * ++count)) < number );
        System.out.println(number + "=" + (number==factorial? "" + count + "!" : "NONE"));
    }
}

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