package threenplusone;

public class HailstoneLengthQuick {
    private int max;

    public static void main(String[] args) {
        HailstoneLengthQuick hlq = new HailstoneLengthQuick();
        // TODO: validate input so we can assume input is in the form 'a, b' where b>=a and b,a>0

        // parse the input into lower and upper bounds for the range on which we want to compute.
        int lower = 1;
        int upper = 2;
        try {
            lower = Integer.parseInt(args[0]);
            upper = Integer.parseInt(args[1]);
        }
        catch (java.lang.ArrayIndexOutOfBoundsException ex) { }

        // the outer loop
        int workingMax = 0;
        for (int n = lower; n <= upper; n++) {
            workingMax = hlq.collatzCount(n);
            if (workingMax > hlq.max) {
                hlq.max = workingMax;
            }
        }

        System.out.println(lower + " " + upper + " " + hlq.max);
    }

    public int collatzCount(int n) {
        int count = 1;
        // the inner loop
        while (n>1) {
            count++;
            if (n%2 == 0) { //n even
                n = n>>1;
            }
            else {
                n = (3*n) + 1;
            }
        }
        return count;
    }

    int getMax() {
        return max;
    }
}