Halvor Strand

public static int gcd(int a, int b)
{
	if(b == 0) return a;
	return gcd(b, a%b);
}

public static int lcm(int a, int b)
{
	return Math.abs(a*b)/gcd(a,b);
}

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public static boolean isPowerOfTwo(int x)
{
	return ((x & (x-1)) == 0);
}

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public static Vector<Integer> primeFactorize(int x)
{
	Vector<Integer> factors = new Vector<Integer>();

	for(int i = 2; i <= Math.sqrt(x); i++)
	{
		while(x%i == 0)
		{
			factors.add(i);
			x /= i;
		}
	}

	if(x > 1)
		factors.add(x);

	return factors;
}

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