public class Main
{
    static long[] doors = new long[100];
 
    public static void main (String[] args)
    {
        for (int i = 0 ; i < 100; i++) {
            for (int j = 0; j < 100; j++) {
                if (((j / (i + 1)) * (i + 1)) == j) {
                    doors[j]++;
                }
            }
        }
 
        for (int i = 0 ; i < 100; i++) {
            if (((doors[i] / 2) * 2) == doors[i]){
 
            } else {
                System.out.println("Door number %s is open".replaceAll("%s", "" + i));
            }
        }
    }
}

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