diff --git a/cpp/_rvmain.cpp b/cpp/_rvmain.cpp
index aad1ed5..0f70993 100644
--- a/cpp/_rvmain.cpp
+++ b/cpp/_rvmain.cpp
@@ -5,6 +5,27 @@
 //int8_t x = 1, y = 2, z[10];
 //int8_t *ip;    /* ip to wskaźnik do obiektu typu int */
 
+void swap_ptr (int8_t *x, int8_t *y) {
+
+    int8_t tmp;
+    tmp = *x;
+    *x = *y;
+    *y = tmp;
+        
+}
+
+// -----------------------------------------------
+
+void swap(int8_t x, int8_t y) {
+
+    int8_t tmp;
+    tmp = x;
+    x = y;
+    y = tmp;
+        
+}
+
+
 int main()  {
 
 //    ip = &x;    /* ip wskazuje teraz x */
@@ -19,6 +40,9 @@ int main()  {
     *mip = 0;    /* x ma teraz wartość 0 */
     mip = &mz[0]; /* ip wskazuje teraz z[0] */
 
+    swap (mx, my);
+    swap_ptr (&mx, &my);
+
   return 1;
 }