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diff --git a/Algorithms/Part-I/5-KdTrees/NearestNeighborVisualizer.java b/Algorithms/Part-I/5-KdTrees/NearestNeighborVisualizer.java
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+/*************************************************************************
+ * Compilation: javac NearestNeighborVisualizer.java
+ * Execution: java NearestNeighborVisualizer input.txt
+ * Dependencies: PointSET.java KdTree.java Point2D.java In.java StdDraw.java
+ *
+ * Read points from a file (specified as a command-line argument) and
+ * draw to standard draw. Highlight the closest point to the mouse.
+ *
+ * The nearest neighbor according to the brute-force algorithm is drawn
+ * in red; the nearest neighbor using the kd-tree algorithm is drawn in blue.
+ *
+ *************************************************************************/
+
+public class NearestNeighborVisualizer {
+
+ public static void main(String[] args) {
+ String filename = args[0];
+ In in = new In(filename);
+
+ StdDraw.show(0);
+
+ // initialize the two data structures with point from standard input
+ PointSET brute = new PointSET();
+ KdTree kdtree = new KdTree();
+ while (!in.isEmpty()) {
+ double x = in.readDouble();
+ double y = in.readDouble();
+ Point2D p = new Point2D(x, y);
+ kdtree.insert(p);
+ brute.insert(p);
+ }
+
+ while (true) {
+
+ // the location (x, y) of the mouse
+ double x = StdDraw.mouseX();
+ double y = StdDraw.mouseY();
+ Point2D query = new Point2D(x, y);
+
+ // draw all of the points
+ StdDraw.clear();
+ StdDraw.setPenColor(StdDraw.BLACK);
+ StdDraw.setPenRadius(.01);
+ brute.draw();
+
+ // draw in red the nearest neighbor (using brute-force algorithm)
+ StdDraw.setPenRadius(.03);
+ StdDraw.setPenColor(StdDraw.RED);
+ brute.nearest(query).draw();
+ StdDraw.setPenRadius(.02);
+
+ // draw in blue the nearest neighbor (using kd-tree algorithm)
+ StdDraw.setPenColor(StdDraw.BLUE);
+ kdtree.nearest(query).draw();
+ StdDraw.show(0);
+ StdDraw.show(40);
+ }
+ }
+}