Logical Operators in C – Different Types with Examples

Learn the logical operators of C Programming and embark upon such a journey. Any decision-making process in C can be the linchpin with these operators, making these the most important C operators in generating complex and dynamic programs. This guide will explain logical operators in C and the three types of logical operators in the C language: AND, OR, and NOT.

From beginning programmers to advanced programming, this communal guide would teach one how to use these operators to manipulate and evaluate expressions. Enhance your coding skills to the next level with this insightful guide.

What is an Operator in Computer Programming?

An operator is a symbol, keyword, or combination that performs specific operations on one or more operands. Operands are data items manipulated by operators. Operators help perform arithmetic calculations, comparisons, or logical evaluations in programming.

In C programming, operators are broadly classified into three categories:

1. Unary Operators

These work on a single operand. Examples include:

• Arithmetic Operators: Increment (++) and decrement (–), which add or subtract 1 from the operand.
• Logical Operators: NOT (!), which reverses the logical state of the operand.
• Bitwise Operators: Bitwise NOT (~), which inverts all the bits of an operand.

2. Binary Operators

Binary operators require two operands. Examples include:

• Arithmetic Operators: Perform addition (+), subtraction (-), multiplication (*), division (/), and modulo (%).
• Relational Operators: Compare values, such as equality (==), not equal (!=), greater than (>), and less than (<).
• Logical Operators: AND (&&) and OR (||).
• Bitwise Operators: AND (&), OR (|), XOR (^), and shift operators (<<, >>).
• Assignment Operators: Assign values or modify variables, like simple assignment (=) and compound assignments (+=, -=, etc).

3. Ternary Operator

This operator works with three operands and has the following syntax:

(condition) ? expression1 : expression2;

It is a shorthand for if…else statements, where expression1 executes if the condition is true, and expression2 executes otherwise.

What are Logical Operators in C?

We use logical operators to execute the logical actions on boolean expressions. A logical operation does produce 0 or 1 as a result. When making decisions in your code, your wise companions in C programming are logical operators. The symbols allow you to merge those multiple conditions into a definitive true or false. The three logical operators, “&&” (logical AND), “||” (logical OR), and “!” (logical NOT), give you the capability to build strained decision structures that lead to agile and somewhat adaptable code.

Using logical operators allows your program’s flow to run more efficiently, smarter, and more effectively. Logical operators in C programming must write efficient and reliable programs that solve different problems depending on the conditions.

Logical Operators and Their Role in C Programming

In C programming, logical operators are very important in performing powerful decision-making operations. These are the list of such operators “&&” (logical AND), “||” (logical OR) and “!” (logical NOT). The usage of the logical AND implies that the overall expression will be true only when both of the conditions are also true. With AND and logical AND, both conditions are required to be true to get the overall expression to be true. On the other hand, with logical OR, at least one condition must be true for the expression to be true. The reverse of the condition’s truth value is the logical NOT.

These powerful logical operators allow you to dictate where your program will direct its flow and approach a decision considering any conditions that may present themselves. To simplify this, let us take an example of an array in C or C++. Logical operators become great allies when checking data, sorting the elements, or finding a given value in arrays. Their versatility makes the world of your code efficient and effective in handling different scenarios.

For an in-depth understanding of how operators work in C programming, refer to “An Introduction Types of Operators.”

Functions of Logical Operators in C

Here are the functions of logical operators in C, explained in human-friendly points:

• Logical AND (“&&”): The logical AND operator in C performs a joint evaluation of two conditions, resulting in true only when both are true. If one or both conditions are false, the overall expression will yield false. In the logical AND, each condition needs to be evaluated to be true to get true as the outcome, ensuring both conditions must always exist for the whole expression to be considered true.
• Logical OR (“||”): Logical OR is an operator, and in C, it is used to check multiple conditions and produces a true output if even one of them is true. However, the overall expression is false only when all the conditions are false.
• Logical NOT (“!”): The operator of the logical NOT reverses the truth value of a condition. If a condition is true, the NOT operator makes it false, and vice versa. It’s like a switch that is either true or false, and it is true or false. Also, read about Java Operators and SQL Operators.

Types of Logical Operators

Below are the major types of logical operators in C with examples:

1. Logical AND Operator (&&)

Syntax: result = condition1 && condition2;

Explanation: The logical AND operator combines two conditions and evaluates to true only if both conditions are true. If either or both conditions are false, the result will be false.

Example:

The program checks whether age and height meet the eligibility criteria in this example. If the age is 18 or above and the height is 160 or above, the person is eligible for the ride.

2. Logical OR Operator (||)

Syntax: result = condition1 || condition2;

Explanation: The logical OR operator allows you to evaluate multiple conditions and yields an accurate result if at least one of the conditions is true. If all conditions are false, the result will be false.

Example:

The program checks whether the temperature is above 30 degrees Celsius or the humidity is above 80%. If at least one of these conditions is true, a message about a hot and humid day will be displayed.

3. Logical NOT Operator (!)

Syntax: result = !condition;

Explanation: The logical NOT operator reverses the truth value of a condition. If a condition is true, the NOT operator makes it false, and vice versa.

Example:

In this example, hasPermission is initially set to 1, which means access is granted. However, using the logical NOT operator, we check the opposite condition in the if statement. So, if hasPermission is not true (i.e., false), the message “Access denied!” will be displayed. Otherwise, the message “Access granted!” will be shown. Moreover, you can also learn what arrays are in C and C++ to expand your knowledge.

Short-Circuit Evaluation

Short-circuit evaluation is a nifty feature provided by logical operators in C programming. When using logical AND (&&) or logical OR (||), the evaluation process might not always require checking both conditions.

• For logical AND (&&): When the first condition is false, the whole expression will be false even if the second condition is true. Thus, C no longer needs to check the second condition, as it would save themselves and their resources through time.
• For logical OR (||): If the first condition is true, the entire expression will succeed regardless of the second condition. Hence, C does not care about the second condition, and the evaluation is faster and more efficient.

Short-circuit evaluation helps optimise your code by avoiding unnecessary computations when the result is already determined based on the first condition. This little trick can significantly improve the performance of your C programs when working with logical operators.

Functions of Logical Operators in C

Here are the functions of logical operators in C, explained in human-friendly points:

• Logical operators: You can combine several conditions in C programming to perform more complex decisions using logical operators.
• Evaluation: They check whether the connected conditions result in truth, i.e. the evaluation is consistent.
• Logical AND (&&): A C expression that involves the AND operator verifies that both conditions match for true and generates the overall true expression only when all the conditions meet simultaneously.
• || or logical OR: OR operator will return true when one of the values is true. The overall expression is false whenever all its conditions are false.
• Logical NOT (!): NOT operator inverts the truth value of a condition. NOT operator if a condition is true; it makes it false and vice versa.

Conclusion

Logical operators in C, such as AND, OR, and NOT, are fundamental to creating effective and efficient code. Understanding and utilising these operators can significantly enhance your programming decision-making capabilities, allowing for more complex and nuanced expressions. We hope this guide has helped resolve these key components and equip you with the knowledge to use them effectively in your coding journey. Get on with this Business Analytics and Data Science in collaboration With edX Aligned with Nasscom course offered by HeroVired, which can help you start your educational path.