uni/inf2440/hw2/Sequential.java

import java.util.ArrayList;

class Sequential implements Solver {
	public void solve(Sieve sieve) {
		sieve.generatePrimes();
	}

	public long[] factor(Sieve sieve, long num) {
		if (num < sieve.maxNum && sieve.isPrime((int)num))
			return new long[] { num };

		int sqrt = (int)Math.sqrt(num);

		ArrayList<Long> arr = new ArrayList<>();

		while (true) {
			long prime;
			for (prime = 2; prime <= sqrt; ++prime) {
				if (num % prime == 0) {
					arr.add(new Long(prime));
					num /= prime;
					break;
				}
			}

			if (prime > sqrt) {
				arr.add(new Long(num));
				break;
			}

			if (num <= sqrt && sieve.isPrime((int)num)) {
				if (num != 1)
					arr.add(new Long(num));
				break;
			}
		}

		long[] a = new long[arr.size()];
		for (int i = 0; i < a.length; ++i) {
			a[i] = arr.get(i);
		}
		return a;
	}
}