What do x-- and --x mean in C language?

The difference between x-- and --x in C language is: x--: After decrement, the original value of x is used first, and then decremented by 1. --x: Pre-decrement, first decrement by 1, and then use the updated value of x.

The difference between x-- and --x in c language

In C language, x-- and --x are both decrement operators, which decrease variable x by 1. They differ in the position of the operator relative to the variable:

• x--: Post-decrement
• --x: Pre-decrement

Post-decrement (x--)

Post-decrement expression will first use the value of variable x for expression or assignment , then subtract 1 from x. For example:

<code class="c">int x = 10;
int y = x--; // y = 10, x = 9</code>

Precede decrement (--x)

Precede decrement expression will first subtract 1 from x, and then use the updated x value in expressions or assignments. For example:

<code class="c">int x = 10;
int y = --x; // y = 9, x = 9</code>

Therefore, if you need to use the original value of variable x first and then decrement it by 1, use x-- (post-decrement) . If you need to immediately decrement x by 1 and then use its updated value, use --x (previous decrement) .

The above is the detailed content of What do x-- and --x mean in C language?. For more information, please follow other related articles on the PHP Chinese website!