Question

What I want to do is just iterate a std::list except for the last element. What I am trying:

#include <cstdlib>
#include <list>

int main() {
  std::list<int> *list = new std::list<int>(100);
  std::list<int>::iterator it;

  for (it = list->begin(); it != list->end()-1; it++) {
    // some action here...
  }
}

However, this will not work. What is wrong?

Answer 1

std::list uses a bidirectional iterator, which doesn’t support operator-. Use std::prev instead:

for (it = list->begin(); it != std::prev(list->end()); it++) {
  // some action here...
}