Facebook Hacker Cup 2013 Round 1 DeadPixels Java

DeadPixels.java

import java.util.LinkedList;
import java.util.List;
import java.util.Scanner;

/**
 * @author psy
 * 
 */
public class DeadPixels {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		List<String> output = new LinkedList<String>();

		DeadPixels testCase = new DeadPixels();

		int games = Integer.parseInt(in.nextLine());

		for (int i = 1; i <= games; i++) {
			int w = in.nextInt();
			int h = in.nextInt();
			int p = in.nextInt();
			int q = in.nextInt();
			int n = in.nextInt();
			int x = in.nextInt();
			int y = in.nextInt();
			int a = in.nextInt();
			int b = in.nextInt();
			int c = in.nextInt();
			int d = in.nextInt();

			int result = testCase.findPositions(w, h, p, q, n, x, y, a, b, c, d);

			output.add("Case #" + i + ": " + result);
		}

		for (String out : output) {
			System.out.println(out);
		}
	}

	public int findPositions(int w, int h, int p, int q, int n, int x, int y, int a, int b, int c, int d) {

		int[] xArray = new int[n];
		int[] yArray = new int[n];

		xArray[0] = x;
		yArray[0] = y;

		for (int i = 1; i < n; i++) {
			xArray[i] = (xArray[i - 1] * a + yArray[i - 1] * b + 1) % w;
			yArray[i] = (xArray[i - 1] * c + yArray[i - 1] * d + 1) % h;
		}

		// find unique positions
		int uniquePositions = 0;

		for (int i = 0; i < w - p + 1; i++) {
			for (int j = 0; j < h - q + 1; j++) {

				int endP = i + p;
				int endQ = j + q;

				boolean fit = true;

				for (int z = 0; z < n; z++) {
					if (xArray[z] >= i && xArray[z] < endP) {
						if (yArray[z] >= j && yArray[z] < endQ) {
							fit = false;
							break;
						}
					}
				}

				if (fit) {
					uniquePositions++;
				}
			}
		}

		return uniquePositions;
	}

}