Note 01: Pre-increment after increment i++;++i;

Before looking at the video course, it is not clear before the increment, after the increment, the amount of pre-decrement, after the reduction of the piece, this now know what happened, need to record down so that later.

1. var m = 10;
2. var n = 8;
3. alert (++m); 11
4. alert (n++); 8
5. Alert (m); 11
6. Alert (m); 9

The pre-increment is calculated before executing the statement that contains the variable m, after which the increment is naturally calculated after executing the statement, so the Code line fourth pops up 8, and the sixth line POPs 9;

The corresponding amount of pre-decrement and post-decrement is also the reason.

The JavaScript Advanced Programming book indicates

Note 01: Pre-increment after increment i++;++i;