What does ?: mean in C language?
The conditional operator ?: in C language is a ternary operator that allows selection between two expressions based on conditions. The syntax is: condition? expr1 : expr2, condition determines whether the expression is executed, expr1 is executed when condition is true, and expr2 is executed when condition is false. Advantages include simplicity and efficiency, but care needs to be taken with nesting, data types, and precedence.
Conditional operator in C language?:
Conditional operator in C language?:, also Called the ternary operator, it is a simplified conditional statement. It can choose between two expressions based on the value of a condition.
Syntax:
condition ? expr1 : expr2
Working principle:
- condition: a Boolean expression Formula, determines whether to execute the operator.
- expr1: If condition is true, this expression is executed.
- expr2: If condition is false, this expression is executed.
Example:
Suppose we have a variable num
and want to determine whether it is even or odd. We can use the ternary operator:
result = (num % 2 == 0) ? "Even" : "Odd";
If num
is an even number and condition
is true, then result
will be assigned the value "Even ". Otherwise, condition
is false and result
will be assigned the value "Odd".
Advantages:
- Simplicity: The ternary operator can succinctly replace certain if-else statements, making the code more readable .
- Efficiency: In some cases, the compiler may optimize the ternary operator to make the code run faster.
Notes:
- Nesting: The ternary operator can be nested, but the code will become difficult read.
-
Data type:
expr1
andexpr2
must return the same data type. - Priority: The ternary operator has a higher priority than the arithmetic operator, but lower than the assignment operator.
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