About c++11 range for loops and iterators

Question

What does the c++11 range for loops do that cause this:

std::list item;
....
//fill the list somewhere else
....
for(Point p : item) {
         


        

Answer 1

In your former code, the line

for(Point p : item) {

creates copies of the point every time you access the next item. To make sure that your calling of method lowerY() works, you need to redefine it as

for(Point & p : item) {