What does a-- mean in c++
The a-- in C is the postfix decrement operator. It calculates, decrements by 1, and updates the value of the variable a, and then decrements its value after the variable is used. Uses include: decrementing loop variables in loops, iterating over elements in arrays and lists, checking the value of a variable and decrementing it.
a--
in C In C, a--
is Postfix decrement operator, which decrements the value of variable a
by 1.
Syntax:
a--;
Working principle:
a--
Decrease in the following steps# Value of ##a:
- First, it calculates the current value of
- a
.
Then, it decrements the value of - a
by 1.
Finally, it assigns the updated value back to - a
.
Note:
- is different from the prefix decrement operator
- --a
,
a--Decrement the value of a variable after using it.
- a--
returns the value after decrementing, while
--areturns the value before decrementing.
Example:
int a = 5; a--; // a 变为 4 cout << a; // 输出 4
Use of postfix decrement operator:
a--Usually used when you need to use the current value of a variable and then decrement it. For example:
- In a loop, used to decrement the loop variable.
- In an array or list, used to iterate through elements.
- In conditional statements, used to check whether a variable is equal to or greater than a certain value and then decrement it.
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