A Guide to C++ Or, And and Not Logical Operators

In modern C++, you can use and, or and not as boolean operators, which means &&, || and ! respectively. This makes them identical to languages like Python. These operators were in C as macros, but modern C++ introduced them as keywords.

#include <iostream>

int main() {

std::cout << true and true << std::endl;
std::cout << true or false << std::endl;
std::cout << not true << std::endl;

 return 0;
}

This is exactly identical to:

#include <iostream>

int main() {

std::cout << true && true << std::endl;
std::cout << true || false << std::endl;
std::cout << !true << std::endl;

 return 0;
}

You can probably use any one of the styles depending on your codebase.

C++ Or, And and Not Logical Operators Explained With Code

Below you’ll find an explanation of how the and, or and not operators in C++ work, along with sample code.

1. And Operator

C++ and operator is used for boolean evaluations between boolean values. It is equivalent to && operator. Both are used to evaluate two expressions and return true only if both expressions are true. Otherwise, it returns false.

And Operator Syntax

bool and bool

And Operator Code Example

#include <iostream>
using namespace std;

int main() {
	bool a = true;
	bool b = false;

	if (a and b) {
    	cout << "Both are true" << endl;
	} else {
    	cout << "One or both are false" << endl;
	}

	return 0;
}

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2.Or Operator

C++ or operator is used for boolean evaluations between boolean values. It is equivalent to the || operator. Both are used to evaluate two expressions and return true only if one expressions is true. Otherwise, it returns false.

Or Operator Syntax

bool or bool

Or Operator Code Example

#include <iostream>
using namespace std;

int main() {
	bool a = true;
	bool b = false;

	if (a or b) {
    	cout << "One is true" << endl;
	} else {
    	cout << "Both are false" << endl;
	}

	return 0;
}

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3. Not Operator

C++ not operator is used to invert boolean values. Not true becomes false and not false becomes true.

Not Operator Syntax

not boolean_value

Not Operator Code Example

#include <iostream>
using namespace std;

int main() {
	bool a = true;
	

	if (not a) {
    	cout << "a is now false" << endl;
	} else {
    	cout << "a is still true" << endl;
	}

	return 0;
}

Even though and, or and not are introduced as keywords, many codebases still use the symbolic form and these should be used when really needed.

Frequently Asked Questions