C Logical Operators
Logical Operators
As with comparison operators, you can also test for true or false values with logical operators.
Logical operators are used to determine the logic between variables or values, by combining multiple conditions:
| Operator | Name | Example | Description | Try it |
|---|---|---|---|---|
| && | AND | x > 3 && x < 10 | Returns 1 if both statements are true | Try it » |
| || | OR | x > 3 || x < 4 | Returns 1 if one of the statements is true | Try it » |
| ! | NOT | !(x > 3 && x < 10) | Reverses the result, returns 0 if the result is 1 | Try it » |
Visualize Logical Operators
Choose values for a and b below to see the result of each logical operator:
Code
Output
Explanation
Real-Life Example: Login Check
The example below shows how logical operators can be used in a real situation, e.g. when checking login status and access rights:
Example
int isLoggedIn = 1;
int isAdmin = 0;
printf("Regular user: %d\n", isLoggedIn && !isAdmin);
printf("Has access: %d\n", isLoggedIn || isAdmin);
printf("Not logged in: %d\n", !isLoggedIn);
Result:
Regular user: 1
Has access: 1
Not logged in: 0
Remember: in C, 1 means true and 0 means false. Logical operators often become easier to understand once you start using them inside if statements, which you will learn about in the upcoming chapters.
