Prefer Pre Dec/Inc over Post Dec/Inc.

[shahzadlone]

Change all post-increments(and post-decrements) to pre-increments(and pre-decrements) to save on copies.

For example consider the following:

class Integer {

  public:

  // Sample implementation of pre-incrementing.
  Integer & operator++() {
    myInt += 1;
    return *this;
  }
  // Sample implementation of post-incrementing.
  const Integer operator++(int) {
    Integer temporary = *this;
    ++*this;
    return temporary;
  }

  private:

  int myInt;
};

The additional copy (temporary) in post-incrementing step is unnecessary (similar case for post-decrementing).

[shahzadlone]

Do I need to provide anything else?