Data commit

Task/Find-the-intersection-of-two-lines/Java/find-the-intersection-of-two-lines.java

@@ -0,0 +1,47 @@
+public class Intersection {
+    private static class Point {
+        double x, y;
+
+        Point(double x, double y) {
+            this.x = x;
+            this.y = y;
+        }
+
+        @Override
+        public String toString() {
+            return String.format("{%f, %f}", x, y);
+        }
+    }
+
+    private static class Line {
+        Point s, e;
+
+        Line(Point s, Point e) {
+            this.s = s;
+            this.e = e;
+        }
+    }
+
+    private static Point findIntersection(Line l1, Line l2) {
+        double a1 = l1.e.y - l1.s.y;
+        double b1 = l1.s.x - l1.e.x;
+        double c1 = a1 * l1.s.x + b1 * l1.s.y;
+
+        double a2 = l2.e.y - l2.s.y;
+        double b2 = l2.s.x - l2.e.x;
+        double c2 = a2 * l2.s.x + b2 * l2.s.y;
+
+        double delta = a1 * b2 - a2 * b1;
+        return new Point((b2 * c1 - b1 * c2) / delta, (a1 * c2 - a2 * c1) / delta);
+    }
+
+    public static void main(String[] args) {
+        Line l1 = new Line(new Point(4, 0), new Point(6, 10));
+        Line l2 = new Line(new Point(0, 3), new Point(10, 7));
+        System.out.println(findIntersection(l1, l2));
+
+        l1 = new Line(new Point(0, 0), new Point(1, 1));
+        l2 = new Line(new Point(1, 2), new Point(4, 5));
+        System.out.println(findIntersection(l1, l2));
+    }
+}