Logical Operators

Logical operators in C++ are used to combine or reverse conditions. They are mainly used in decision-making statements like if, while, and loops.

What are Logical Operators?

Logical operators work with boolean expressions and return:

• true (1)
• false (0)

They help combine multiple conditions in a program.

Types of Logical Operators in C++

Operator	Meaning
&&	Logical AND
`
!	Logical NOT

Logical AND Operator (&&)

The AND operator returns true only if both conditions are true.

Example

#include <iostream>
using namespace std;

int main() {
    int a = 10;
    int b = 5;

    cout << (a > 5 && b < 10);

    return 0;
}

Output

1

Logical OR Operator (||)

The OR operator returns true if at least one condition is true.

Example

#include <iostream>
using namespace std;

int main() {
    int a = 10;
    int b = 20;

    cout << (a > 5 || b < 10);

    return 0;
}

Output

1

Logical NOT Operator (!)

The NOT operator reverses the result:

• true becomes false
• false becomes true

Example

#include <iostream>
using namespace std;

int main() {
    bool value = true;

    cout << !value;

    return 0;
}

Output

0

Complete Example Program

#include <iostream>
using namespace std;

int main() {
    int age = 20;
    int marks = 80;

    cout << (age >= 18 && marks >= 50) << endl;
    cout << (age < 18 || marks >= 50) << endl;
    cout << !(age >= 18) << endl;

    return 0;
}

Output

1
1
0

Truth Table of Logical Operators

A	B	A && B	A || B
0	0	0	0
0	1	0	1
1	0	0	1
1	1	1	1

Using Logical Operators in Conditions

Example

if (username == "admin" && password == "1234") {
    cout << "Login Successful";
}

Important Points

• Logical operators work with conditions
• They return boolean results
• Used in decision-making and loops
• && needs all conditions true
• || needs at least one condition true

Why Logical Operators are Important

They are important because they:

• Combine multiple conditions
• Control program flow
• Help in complex decision-making
• Improve programming logic

Real-Life Example

Logical operators are used in:

• Login systems
• Exam eligibility checking
• Game conditions
• Security systems
• Banking applications

Conclusion

Logical operators in C++ are essential for combining and controlling conditions in programs. They help create smart and interactive applications by allowing programs to make logical decisions efficiently.