C++ Logical Operators

Logical operators perform logical operations on Boolean values or expressions. These operators are used to combine two or more conditions and help in decision-making.

Types of Logical Operators

C++ provides three logical operators:

• Logical AND (&&)
• Logical OR (||)
• Logical NOT (!)

1. Logical AND (&&)

The logical AND operator returns true only if both operands are true. If any operand is false, the result is false.

The syntax of logical AND is:

condition_1 && condition 2

2. Logical OR (||)

The logical OR operator returns true if at least one of the conditions is true. If both are false, it returns false.

The syntax of logical OR is:

condition_1 || condition 2

3. Logical NOT (!)

The logical NOT operator negates the given condition. If a condition is true, it returns false and vice versa.

The syntax of logical NOT is:

!condition

Example of Logical Operators

Try the following example to understand all the logical operators available in C++.

Copy and paste the following C++ program in test.cpp file and compile and run this program.

#include <iostream>
using namespace std;

main() {
   int a = 5;
   int b = 20;
   int c ;

   if(a && b) {
      cout << "Line 1 - Condition is true"<< endl ;
   }
   
   if(a || b) {
      cout << "Line 2 - Condition is true"<< endl ;
   }
   
   /* Let's change the values of  a and b */
   a = 0;
   b = 10;
   
   if(a && b) {
      cout << "Line 3 - Condition is true"<< endl ;
   } else {
      cout << "Line 4 - Condition is not true"<< endl ;
   }
   
   if(!(a && b)) {
      cout << "Line 5 - Condition is true"<< endl ;
   }
   
   return 0;
}

When the above code is compiled and executed, it produces the following result −

Line 1 - Condition is true
Line 2 - Condition is true
Line 4 - Condition is not true
Line 5 - Condition is true