PHP basic syntax: self-increment and self-decrement

Question

Are the values ​​of self-increasing and self-decreasing all 1?

Answer 1

Self-increment: $a++ is equivalent to $a+1

Self-decrement: $a-- is equivalent to $a-1

Answer 2

The value of each influence of self-increasing and self-decreasing is 1

Answer 3

$i++
//类似这样的代码，就是自加一