[백준] 17386번 : 선분 교차1 - Java(자바)

https://www.acmicpc.net/problem/17386

import java.util.Scanner;
public class Main {
    static int ccw(long v1, long w1, long v2, long w2, long v3, long w3){
        return (v1*w2+v2*w3+v3*w1)-(v2*w1+v3*w2+v1*w3)<0 ? 1 : -1;
    }
    public static void main(String args[]) {
        Scanner s=new Scanner(System.in);
        int x1=s.nextInt(), y1=s.nextInt(), x2=s.nextInt(), y2=s.nextInt();
        int x3=s.nextInt(), y3=s.nextInt(), x4=s.nextInt(), y4=s.nextInt();
        
        int a1=ccw(x1,y1,x2,y2,x3,y3)*ccw(x1,y1,x2,y2,x4,y4);
        int a2=ccw(x3,y3,x4,y4,x1,y1)*ccw(x3,y3,x4,y4,x2,y2);
        
        if(a1<0 && a2<0) System.out.print("1");
        else System.out.print("0");
    }
}