// Let's Learn C++ - Rademaker Robin - Edited on 15/02/2019 // Code of the day on 15/02/2019 - Thank you very much! #include using namespace std; /* About pointers: */ // This is a function which is used later on void pointFunc(int *x) { *x += 10; // *x = *x + 10; (same as above) // *x + 10; (doesn't add 10 to *x) } int main() { // In this example we use *pSum to point to the value of iSum // Whatever happens to iSum, the value is pointed to *pSum int iSum = 0; int iNum = 2; int *pSum = &iSum; iSum += iNum; iSum *= iNum; cout << "Value of iSum: " << iSum << endl; cout << "Value of *pSum: " << *pSum << "\n\n"; // Now we alter the outcome of iSum some more iSum *= iSum; // We get the point now cout << "Value of iSum: " << iSum << endl; cout << "Value of *pSum: " << *pSum << "\n\n"; // This Function makes use of pass-by-reference // this copies an argument's address into the function parameter // Inside the function, the address is used to access the actual argument, in this case // the current value of num2. int num2 = 20; pointFunc(&num2); // important is the use the use of & same as with pointers cout << "The value of num2 changes to the value of *x in pointFunc\n" << "because *x has access to the value of num2: " << num2 << "\n\n"; // We can also use our previous variable iSum pointFunc(&iSum); cout << "If we use iSum then *x in pointFunc has access to\n" << "the value of iSum (which was 16) is now: " << iSum << "\n\n"; // Let's see what happens to the value of *pSum, still pointing to iSum cout << "Value of *pSum is still equal to iSum: " << *pSum << "\n\n"; return 0; }

Cpp - Lets learn about pointers - COTD