From 60d3bf03904bc4f691d98b63ece8a1a7a482f182 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=A9r=C3=A9my=20Zurcher?= <jeremy@asynk.ch>
Date: Wed, 27 Mar 2013 16:59:00 +0100
Subject: Algorithms-I : 5-KdTrees: nearest must use local variables

---
 Algorithms/Part-I/5-KdTrees/KdTree.java | 44 +++++++++++++++++----------------
 1 file changed, 23 insertions(+), 21 deletions(-)

diff --git a/Algorithms/Part-I/5-KdTrees/KdTree.java b/Algorithms/Part-I/5-KdTrees/KdTree.java
index 3607976..d0c0fcd 100644
--- a/Algorithms/Part-I/5-KdTrees/KdTree.java
+++ b/Algorithms/Part-I/5-KdTrees/KdTree.java
@@ -192,13 +192,15 @@ public class KdTree
         return nearest(root, p, null, Double.MAX_VALUE, true);
     }
 
-    private Point2D nearest(Node n, Point2D p, Point2D ncp, double d, boolean vsplit)
+    private Point2D nearest(Node n, Point2D p, Point2D cp, double d, boolean vsplit)
     {
+        Point2D cp0 = cp;
+        double d1 = d;
         double d2 = p.distanceSquaredTo(n.p);
-        if (d2 < d)
+        if (d2 < d1)
         {
-            ncp = n.p;
-            d = d2;
+            cp0 = n.p;
+            d1 = d2;
         }
 
         if (vsplit)
@@ -208,21 +210,21 @@ public class KdTree
             {
                 if (n.left != null)
                 {
-                    ncp = nearest(n.left, p, ncp, d, !vsplit);
-                    d = p.distanceSquaredTo(ncp);
+                    cp0 = nearest(n.left, p, cp0, d1, !vsplit);
+                    d1 = p.distanceSquaredTo(cp0);
                 }
-                if (n.right != null && ((d2 * d2) < d))
-                    ncp = nearest(n.right, p, ncp, d, !vsplit);
+                if (n.right != null && ((d2 * d2) < d1))
+                    cp0 = nearest(n.right, p, cp0, d1, !vsplit);
             }
             else
             {
                 if (n.right != null)
                 {
-                    ncp = nearest(n.right, p, ncp, d, !vsplit);
-                    d = p.distanceSquaredTo(ncp);
+                    cp0 = nearest(n.right, p, cp0, d1, !vsplit);
+                    d1 = p.distanceSquaredTo(cp0);
                 }
-                if (n.left != null && ((d2 * d2) < d))
-                    ncp = nearest(n.left, p, ncp, d, !vsplit);
+                if (n.left != null && ((d2 * d2) < d1))
+                    cp0 = nearest(n.left, p, cp0, d1, !vsplit);
             }
         }
         else
@@ -232,24 +234,24 @@ public class KdTree
             {
                 if (n.left != null)
                 {
-                    ncp = nearest(n.left, p, ncp, d, !vsplit);
-                    d = p.distanceSquaredTo(ncp);
+                    cp0 = nearest(n.left, p, cp0, d1, !vsplit);
+                    d1 = p.distanceSquaredTo(cp0);
                 }
-                if (n.right != null && ((d2 * d2) < d))
-                    ncp = nearest(n.right, p, ncp, d, !vsplit);
+                if (n.right != null && ((d2 * d2) < d1))
+                    cp0 = nearest(n.right, p, cp0, d1, !vsplit);
             }
             else
             {
                 if (n.right != null)
                 {
-                    ncp = nearest(n.right, p, ncp, d, !vsplit);
-                    d = p.distanceSquaredTo(ncp);
+                    cp0 = nearest(n.right, p, cp0, d1, !vsplit);
+                    d1 = p.distanceSquaredTo(cp0);
                 }
-                if (n.left != null && ((d2 * d2) < d))
-                    ncp = nearest(n.left, p, ncp, d, !vsplit);
+                if (n.left != null && ((d2 * d2) < d1))
+                    cp0 = nearest(n.left, p, cp0, d1, !vsplit);
             }
         }
-        return ncp;
+        return cp0;
     }
 
 }
-- 
cgit v1.1-2-g2b99