restructure and add ipi texs

ws2019/ipi/uebungen/cpp_headers/PtrTest.cc

@@ -0,0 +1,19 @@
+#include<iostream>
+
+#include"Ptr.hh"
+
+int g (Ptr<int> p) {
+  return *p;
+}
+
+int main ()
+{
+  Ptr<int> q = new int(17);
+  std::cout << *q << std::endl;
+  int x = g(q);
+  std::cout << x << std::endl;
+  Ptr<int> z = new int(22);
+  q = z;
+  std::cout << *q << std::endl;
+  // nun wird alles automatisch geloescht !
+}