From 6a686933faddf7f2e2b96f3ffe0163c330249981 Mon Sep 17 00:00:00 2001
From: Hans Buchmann <hans.buchmann@fhnw.ch>
Date: Thu, 19 Nov 2020 11:38:09 +0100
Subject: [PATCH] other as pointer

---
 6-cia/src/geo2d-vz.cc | 27 +++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/6-cia/src/geo2d-vz.cc b/6-cia/src/geo2d-vz.cc
index 8c93f0e..598e178 100644
--- a/6-cia/src/geo2d-vz.cc
+++ b/6-cia/src/geo2d-vz.cc
@@ -15,7 +15,7 @@ class Point
                             //non default constructor
   Point(const Point& other); //copy constructor
  ~Point();                 //destructor no parameters
-  double distance(Point other);
+  double distance(Point* other); //other is a pointer
   
   static double distance(Point p,Point q);
  private:
@@ -50,11 +50,15 @@ double Point::distance(Point p,Point q) //is not a member of Point
                 //   |private
 }
 
-double Point::distance(Point other)     //is a member of Point
+double Point::distance(Point* other)     //is a member of Point
 {
- return std::hypot(xc-other.xc,
-                   yc-other.yc);
-} //destructor of other
+ return std::hypot(xc-(*other).xc,  //deref with *
+                   yc- other->yc);  //deref with ->
+/* other notation
+ return std::hypot(xc-other->xc,
+                   yc-other->yc);
+*/		   
+} 
 
 //---------------------------------------------- Line
 
@@ -76,8 +80,19 @@ destructor of Point 6,8       other
 d=5
 destructor of Point 6,8  q
 destructor of Point 3,4 p
+
 */
 
+/* with other as pointer
+constructor of Point 3,4 p
+constructor of Point 6,8 q
+d=5
+destructor of Point 6,8  q
+destructor of Point 3,4  p
+
+*/
+
+
 int main(int argc,char**args)
 {
  Point p(3,4);
@@ -85,7 +100,7 @@ int main(int argc,char**args)
 /*
  distance (3,4) -> (6,8) = sqrt(3*3+4*4)=sqrt(25)=5
 */ 
- auto d1=p.distance(q);          
+ auto d1=p.distance(&q); //address of q *no* copy          
  std::cout<<"d="<<d1<<"\n";
  return 0;
 }
-- 
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