// CS 1538 Fall 2009
// See comments in Rand1.java handout out previously.
// I added methods here to allow output as doubles, both in 16-bits
// and in 32-bits

public class Rand2
{

	private final long mask  = (1L << 32) - 1; 		// this is "m" = 2^32
	private final long multiplier = 1194211693L; 	// this is "a"
	private final long adder = 12345L;				// this is "c"
    private long randSeed;

    public Rand2()
    {
		randSeed = System.currentTimeMillis();
	}

    public Rand2(long s)
    {
		randSeed = s;
	}

    public int nextShort(int n)
	{
		randSeed = (multiplier * randSeed + adder) & mask;
		int shortAns = Math.abs((int) randSeed >> 16);
		return (shortAns % n);
	}

	public double nextDouble()
	{
		randSeed = (multiplier * randSeed + adder) & mask;
		int shortAns = Math.abs((int) randSeed >> 16);
		return ((double)shortAns/65536);
	}

	public double nextDouble32()
	{
		randSeed = (multiplier * randSeed + adder) & mask;
		long intAns = Math.abs(randSeed);
		return ((double)intAns/(mask+1));
	}

}