+// more pointers
+ #include <iostream>
+ using namespace std;
+
+ int main ()
+ {
+ int firstvalue = 5, secondvalue = 15;
+ int * p1, * p2;
+
+ p1 = &firstvalue; // p1 = address of firstvalue
+ p2 = &secondvalue; // p2 = address of secondvalue
+ *p1 = 10; // value pointed to by p1 = 10
+ *p2 = *p1; // value pointed to by p2 = value pointed to by p1
+ p1 = p2; // p1 = p2 (value of pointer is copied)
+ *p1 = 20; // value pointed to by p1 = 20
+
+ cout << "firstvalue is " << firstvalue << '\n';
+ cout << "secondvalue is " << secondvalue << '\n';
+ return 0;
+ }