### 8.7 Increment Operators ¶

Increment operators increase or decrease the value of a variable by 1. The operator to increment a variable is written as ‘`++`’. It may be used to increment a variable either before or after taking its value.

For example, to pre-increment the variable x, you would write `++x`. This would add one to x and then return the new value of x as the result of the expression. It is exactly the same as the expression `x = x + 1`.

To post-increment a variable x, you would write `x++`. This adds one to the variable x, but returns the value that x had prior to incrementing it. For example, if x is equal to 2, the result of the expression `x++` is 2, and the new value of x is 3.

For matrix and vector arguments, the increment and decrement operators work on each element of the operand.

The increment and decrement operators must "hug" their corresponding variable. That means, no white spaces are allowed between these operators and the variable they affect.

Here is a list of all the increment and decrement expressions.

`++x` ¶

  This expression increments the variable x. The value of the expression is the new value of x. It is equivalent to the expression `x = x + 1`.

`--x` ¶

  This expression decrements the variable x. The value of the expression is the new value of x. It is equivalent to the expression `x = x - 1`.

`x++` ¶

  This expression causes the variable x to be incremented. The value of the expression is the old value of x.

`x--` ¶

  This expression causes the variable x to be decremented. The value of the expression is the old value of x.