Problem:
Intersection

For given two segments s1 and s2, print "1" if they are intersect, "0" otherwise.

s1 is formed by end points p0 and p1, and
s2 is formed by end points p2 and p3.

Input

The entire input looks like:

q (the number of queries)
1st query
2nd query
...
qth query

Each query consists of integer coordinates of end points of s1 and s2 in the following format:

xp0 yp0 xp1 yp1 xp2 yp2 xp3 yp3

Output

For each query, print "1" or "0".

Constraints

1 ≤ q ≤ 1000

-10000 ≤ xpi, ypi ≤ 10000

p0 ≠ p1 and
p2 ≠ p3.

Sample Input 1

3
0 0 3 0 1 1 2 -1
0 0 3 0 3 1 3 -1
0 0 3 0 3 -2 5 0

Sample Output 1

1
1
0

Solution in JAVA (judge verdict: Wrong Answer)

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Scanner;

class Main {

	static int n;
	static double[] x1, y1, x2, y2;
	static double sx, sy, gx, gy;
	static ArrayList<Integer>[] g;

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int q = sc.nextInt();
		while (q-- > 0) {
			double x0, y0, x1, y1, x2, y2, x3, y3;
			x0 = sc.nextDouble();
			y0 = sc.nextDouble();
			x1 = sc.nextDouble();
			y1 = sc.nextDouble();
			x2 = sc.nextDouble();
			y2 = sc.nextDouble();
			x3 = sc.nextDouble();
			y3 = sc.nextDouble();
			Point p0 = new Point(x0, y0);
			Point p1 = new Point(x1, y1);
			Point p2 = new Point(x2, y2);
			Point p3 = new Point(x3, y3);
			if (linesIntersect(p0, p1, p2, p3)) {
				System.out.println(1);
			} else {
				System.out.println(0);
			}
		}
		// ArrayList<Point> ps = new ArrayList<>();
		// n = sc.nextInt();
		// x1 = new double[n];
		// y1 = new double[n];
		// x2 = new double[n];
		// y2 = new double[n];
		// for (int i = 0; i < n; ++i) {
		// x1[i] = sc.nextDouble();
		// y1[i] = sc.nextDouble();
		// x2[i] = sc.nextDouble();
		// y2[i] = sc.nextDouble();
		// ps.add(new Point(x1[i], y1[i]));
		// ps.add(new Point(x2[i], y2[i]));
		// }
		//
		// for (int i = 0; i < n; ++i) {
		// for (int j = i + 1; j < n; ++j) {
		//
		// }
		// }

	}

	static class Point {
		double x, y;
		int id;

		public Point(double x, double y) {
			this.x = x;
			this.y = y;
		}
	}

	static boolean linesIntersect(Point s1, Point d1, Point s2, Point d2) {
		return ((crossProduct(s1, d1, s1, d2) * crossProduct(s1, d1, s1, s2)) <= 0)
				&& ((crossProduct(s2, d2, s2, s1) * crossProduct(s2, d2, s2, d1) <= 0));
	}

	static double crossProduct(Point s1, Point d1, Point s2, Point d2) {
		return (d1.x - s1.x) * (d2.y - s2.y) - (d1.y - s1.y) * (d2.x - s2.x);
	}

	static void tr(Object... objects) {
		System.out.println(Arrays.deepToString(objects));
	}
}